firmware: xilinx: Add Versal NET platform compatible string

Introduce a compatible string for the Versal NET platform which enables
platform identification based on the compatible property for platform
specific configurations.

Signed-off-by: Jay Buddhabhatti <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Michal Simek <[e-mail]>

drivers/firmware/xilinx/zynqmp.c

···
 static const struct of_device_id zynqmp_firmware_of_match[] = {
 	{.compatible = "xlnx,zynqmp-firmware"},
 	{.compatible = "xlnx,versal-firmware"},
+	{.compatible = "xlnx,versal-net-firmware"},
 	{},
 };
 MODULE_DEVICE_TABLE(of, zynqmp_firmware_of_match);