sunxi: SPL SPI: Add SPI boot support for the Allwinner R528/T113 SoCs

R528/T113 SoCs uses the same SPI IP as the H6, also have the same clocks
and reset bits layout, but the CCU base is different. Another difference
is that the new SoCs do not have a clock divider inside. Instead of this
we should configure sample mode depending on input clock rate.

The pin assignment is also different: the H6 uses PC0, the R528/T113 PC4
instead. This makes for a change in spi0_pinmux_setup() routine.

This patch extends the H6/H616 #ifdef guards to also cover the R528/T113,
using the shared CONFIG_SUNXI_GEN_NCAT2 and CONFIG_MACH_SUN8I_R528
symbols. Also use CONFIG_SUNXI_GEN_NCAT2 symbol for the Kconfig
dependency.

Signed-off-by: Maksim Kiselev <bigunclemax@gmail.com>
Tested-by: Sam Edwards <CFSworks@gmail.com>