feat(versal-net): add SDEI support

Add basic SDEI support with following configuration settings:
- SGI 8 as the source IRQ.
- Special Private event 0.
- One private and shared dynamic event used in tftf verification
  for SDEI support.
- SDEI support is off by default.

Change-Id: I7cfafb84c3fc053ec67258698cf749e63486fe18
Signed-off-by: Amit Nagal <amit.nagal@amd.com>
diff --git a/plat/xilinx/versal_net/platform.mk b/plat/xilinx/versal_net/platform.mk
index eda3e36..5e8f2b4 100644
--- a/plat/xilinx/versal_net/platform.mk
+++ b/plat/xilinx/versal_net/platform.mk
@@ -145,3 +145,10 @@
 				${LIBFDT_SRCS}					\
 				${PLAT_PATH}/sip_svc_setup.c			\
 				${XLAT_TABLES_LIB_SRCS}
+
+SDEI_SUPPORT := 0
+EL3_EXCEPTION_HANDLING := $(SDEI_SUPPORT)
+ifeq (${SDEI_SUPPORT},1)
+BL31_SOURCES		+=	plat/common/aarch64/plat_ehf.c          \
+				plat/xilinx/versal_net/versal_net_sdei.c
+endif