fpga: zynqmp: support loading authenticated images

Add supporting new compatible string "u-boot,zynqmp-fpga-ddrauth" to
handle loading authenticated images (DDR).

Based on solution by Jorge Ramirez-Ortiz <jorge@foundries.io>

Signed-off-by: Oleksandr Suvorov <oleksandr.suvorov@foundries.io>
Tested-by: Ricardo Salveti <ricardo@foundries.io>
Link: https://lore.kernel.org/r/20220722141614.297383-13-oleksandr.suvorov@foundries.io
Signed-off-by: Michal Simek <michal.simek@amd.com>
diff --git a/include/xilinx.h b/include/xilinx.h
index e5f6db3..97ee12c 100644
--- a/include/xilinx.h
+++ b/include/xilinx.h
@@ -39,6 +39,7 @@
 
 /* FPGA bitstream supported types */
 #define FPGA_LEGACY			BIT(0)
+#define FPGA_XILINX_ZYNQMP_DDRAUTH	BIT(1)
 
 typedef struct {		/* typedef xilinx_desc */
 	xilinx_family family;	/* part type */