Merge tag 'xgene-dts-for-v4.6-part2' of https://github.com/AppliedMicro/xgene-next into next/dt64

Merge "Second part of X-Gene DT changes queued for v4.6" from Duc Dang:

This patch set includes:
+ X-Gene v2 Mailbox DT node
+ X-Gene v1 and X-Gene v2 SLIMpro Mailbox
I2C driver DT nodes

* tag 'xgene-dts-for-v4.6-part2' of https://github.com/AppliedMicro/xgene-next:
  arm64: dts: apm: Add DT node for X-Gene v2 SLIMpro Mailbox I2C Driver
  arm64: dts: apm: Mailbox device tree node for APM X-Gene v2 platform.
  arm64: dts: apm: Add DT node for X-Gene v1 SLIMpro Mailbox I2C Driver
  arm64: dts: apm: mailbox device tree node for APM X-Gene platform.