firmware: xilinx: Add zynqmp IOCTL API for device control

Add ZynqMP firmware IOCTL API to control and configure
devices like PLLs, SD, Gem, etc.

Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Signed-off-by: Jolly Shah <jollys@xilinx.com>
Acked-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>