kernel: Add mailbox and LPC drivers

Mailbox and LPC drivers:

 drivers/mailbox: Add Aspeed mailbox driver
 drivers/misc: Add Aspeed LPC control driver
 dt-bindings: Add Aspeed LPC Control bindings
 dt-bindings: Add Aspeed mailbox bindings

Enable the devices for Zaius and Witherspoon:

 ARM: dts: aspeed-bmc-opp-witherspoon: Enable mailbox and LPC control
 ARM: dts: aspeed-bmc-opp-zaius: Enable mailbox and LPC control node
 ARM: dts: aspeed-g5: Add mailbox and LPC control node

Change-Id: I8030404c5c2f6d90935bbd6b26de7143f564f06d
Signed-off-by: Joel Stanley <joel@jms.id.au>
2 files changed