ARM: dts: aspeed: g220a: Enable secondary flash

Enable the secondary flash of the g220a's BMC and the wdt2.

Signed-off-by: Lei YU <yulei.sh@bytedance.com>
Link: https://lore.kernel.org/r/20211210093623.2140640-1-yulei.sh@bytedance.com


Signed-off-by: Joel Stanley <joel@jms.id.au>