firmware: xilinx: Add query data API

Add ZynqMP firmware query data API to query platform
specific information(clocks, pins) from firmware.

Signed-off-by: Rajan Vaja <rajanv@xilinx.com>
Signed-off-by: Jolly Shah <jollys@xilinx.com>
Signed-off-by: Michal Simek <michal.simek@xilinx.com>