ARM: mstar: Select ARM_ERRATA_814220

All of the SoCs that are supported so far are Cortex A7 r0p5.
So it seems like this errata is present.

Signed-off-by: Daniel Palmer <daniel@0x0f.com>
Reviewed-by: Romain Perier <romain.perier@gmail.com>
Link: https://lore.kernel.org/r/20220223064807.261878-1-daniel@0x0f.com'
Signed-off-by: Arnd Bergmann <arnd@arndb.de>