firmware: xilinx: add register notifier in zynqmp firmware

In zynqmp-firmware, register notifier is not supported, add support of
register notifier in zynqmp-firmware.

Acked-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Tejas Patel <tejas.patel@xilinx.com>
Signed-off-by: Abhyuday Godhasara <abhyuday.godhasara@xilinx.com>
Link: https://lore.kernel.org/r/20211026042525.26612-2-abhyuday.godhasara@xilinx.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>