spi: sun6i: Fix define for SUN6I_TFR_CTL_CS_MASK

Current code in sun6i_spi_set_cs() actually clears CPHA and CPOL bits which is
obvious wrong. The define for SUN6I_TFR_CTL_CS_MASK is wrong. Fix it.

Signed-off-by: Axel Lin <axel.lin@ingics.com>
Acked-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
spi: sunxi: Add Allwinner A10 SPI controller driver

The older Allwinner SoCs (A10, A13, A10s and A20) all have the same SPI
controller.

Unfortunately, this SPI controller, even though quite similar, is significantly
different from the recently supported A31 SPI controller (different registers
offset, split/merged registers, etc.). Supporting both controllers in a single
driver would be unreasonable, hence the addition of a new driver.

Like its more recent counterpart, it supports DMA, but the driver only does PIO
until we have a dmaengine driver for this platform.

Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>
Signed-off-by: Mark Brown <broonie@linaro.org>
Merge remote-tracking branch 'spi/topic/sunxi' into sunxi-next