Merge tag 'zynqmp-soc-for-v5.6' of https://github.com/Xilinx/linux-xlnx into arm...

arm64: soc: ZynqMP SoC changes for v5.6

- Extend firmware interface for feature checking
- Use mailbox for communication with firmware for power management

* tag 'zynqmp-soc-for-v5.6' of https://github.com/Xilinx/linux-xlnx:
  drivers: soc: xilinx: Use mailbox IPI callback
  dt-bindings: power: reset: xilinx: Add bindings for ipi mailbox
  drivers: firmware: xilinx: Add support for feature check

Link: https://lore.kernel.org/r/f6fb26f8-b00d-a3e8-bf7d-c7ff2a8483b1@monstr.eu
Signed-off-by: Olof Johansson <olof@lixom.net>