ARM: multi_v7_defconfig: Enable Actions Semi platform and drivers

The support for Actions Semi ARM32 platform has matured enough in the
mainline. So let's enable it in multi_v7_defconfig along with the
relevant drivers. The platform can now boot a distro from eMMC or uSD
without any out of tree patch.

Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Link: https://lore.kernel.org/r/20210121061447.26517-1-manivannan.sadhasivam@linaro.org'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>