dmaengine: Mark device_control and device_slave_caps as deprecated

Now that device_control has been split into several functions, and
device_slave_caps rendered useless, we can consider them deprecated.

That also means that we don't want to make device_control mandatory any more.
Since any device was free to implement any command of device_control, the only
least common denominator is to not expect any callback anymore.

Hopefully, the generic device_slave_caps can provide such informations to the
client.

Also add warning that trigger during registration if those callbacks are set,
in order to encourage legacy driver to switch to these new mechanisms.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
dmaengine: pl08x: Split device_control

Split the device_control callback of the AMBA PL08x DMA driver to make use
of the newly introduced callbacks, that will eventually be used to retrieve
slave capabilities.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
dmaengine: hdmac: Split device_control

Split the device_control callback of the Atmel HDMAC driver to make use
of the newly introduced callbacks, that will eventually be used to retrieve
slave capabilities.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
dmaengine: bcm2835: Split device_control

Split the device_control callback of the Broadcom BCM2835 DMA driver to make
use of the newly introduced callbacks, that will eventually be used to retrieve
slave capabilities.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
dmaengine: coh901318: Split device_control

Split the device_control callback of the ST-Ericsson COH901318 DMA driver to
make use of the newly introduced callbacks, that will eventually be used to
retrieve slave capabilities.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
dmaengine: cppi41: Split device_control

Split the device_control callback of the TI CPPI41 DMA driver to make use
of the newly introduced callbacks, that will eventually be used to retrieve
slave capabilities.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
dmaengine: jz4740: Split device_control

Split the device_control callback of the JZ4740 DMA driver to make use of the
newly introduced callbacks, that will eventually be used to retrieve slave
capabilities.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
dmaengine: dw: Split device_control

Split the device_control callback of the DesignWare DMA driver to make use
of the newly introduced callbacks, that will eventually be used to retrieve
slave capabilities.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
dmaengine: edma: Split device_control

Split the device_control callback of the TI EDMA driver to make use of the
newly introduced callbacks, that will eventually be used to retrieve slave
capabilities.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
dmaengine: ep93xx: Split device_control

Split the device_control callback of the Cirrus Logic EP93xx driver to make use
of the newly introduced callbacks, that will eventually be used to retrieve
slave capabilities.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
dmaengine: fsl-edma: Split device_control

Split the device_control callback of the Freescale EDMA driver to make use
of the newly introduced callbacks, that will eventually be used to retrieve
slave capabilities.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
dmaengine: imx: Split device_control

Split the device_control callback of the Freescale IMX DMA driver to make use
of the newly introduced callbacks, that will eventually be used to retrieve
slave capabilities.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
dmaengine: imx-sdma: Split device_control

Split the device_control callback of the Freescale IMX SDMA driver to make use
of the newly introduced callbacks, that will eventually be used to retrieve
slave capabilities.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
dmaengine: intel-mid-dma: Split device_control

Split the device_control callback of the Intel MID DMA driver to make use
of the newly introduced callbacks, that will eventually be used to retrieve
slave capabilities.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
dmaengine: ipu-idmac: Split device_control

Split the device_control callback of the IPU IDMAC driver to make use
of the newly introduced callbacks, that will eventually be used to retrieve
slave capabilities.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
dmaengine: k3: Split device_control

Split the device_control callback of the Hisilicon K3 DMA driver to make use
of the newly introduced callbacks, that will eventually be used to retrieve
slave capabilities.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
dmaengine: mmp-pdma: Split device_control

Split the device_control callback of the Marvell MMP PDMA driver to make use
of the newly introduced callbacks, that will eventually be used to retrieve
slave capabilities.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
dmaengine: mmp-tdma: Split device_control

Split the device_control callback of the Marvell MMP TDMA driver to make use
of the newly introduced callbacks, that will eventually be used to retrieve
slave capabilities.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
dmaengine: moxart: Split device_control

Split the device_control callback of the Moxart DMA driver to make use of the
newly introduced callbacks, that will eventually be used to retrieve slave
capabilities.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
dmaengine: fsl-dma: Split device_control

Split the device_control callback of the Freescale Elo DMA driver to make use
of the newly introduced callbacks, that will eventually be used to retrieve
slave capabilities.

While we're at it, remove the useless prep_sg callback.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>