ARM: sunxi: Add basic A23 support

The basic blocks of the A23 are similar to the A31 (sun6i). Re-use
sun6i code for initial clock, gpio, and uart setup.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
ARM: sunxi: Add support for R_PIO gpio banks

The A31, A23 and later SoCs have an extra pin controller, called CPUs_PIO
or R_PIO, which handles pin banks L and beyond.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
[wens@csie.org: expanded commit message]
[wens@csie.org: add pin bank M and expand comments]
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
ARM: sunxi: Allow specifying module in prcm apb0 init function

The prcm apb0 controls multiple modules. Allow specifying which
modules to enable clocks and de-assert resets so the function
can be reused.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
ARM: sunxi: Add support for using R_UART as console

The A23 only has UART0 muxed with MMC0. Some of the boards we
encountered expose R_UART as a set of pads.

Add support for R_UART so we can have a console while using mmc.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
ARM: sunxi: Add Ippo-q8h-v5 A23 tablet board defconfig

Ippo q8h is a series of A23 tablet boards. This defconfig
is for v5 of these boards, though for u-boot purposes they
are mostly the same.

See: http://linux-sunxi.org/Ippo_q8h

Signed-off-by: Chen-Yu Tsai <wens@csie.org>