fix(xilinx): declare unused parameters as void

This corrects the MISRA violation C2012-2.7:
There should be no unused parameters in functions.
Declared unused function parameters as void.

Change-Id: I1d369d977e0f2749024736d53fbb5c7d5555f6cb
Signed-off-by: Nithin G <nithing@amd.com>
Signed-off-by: Maheedhar Bollapalli <MaheedharSai.Bollapalli@amd.com>
diff --git a/plat/xilinx/common/ipi_mailbox_service/ipi_mailbox_svc.c b/plat/xilinx/common/ipi_mailbox_service/ipi_mailbox_svc.c
index 434cd88..6265928 100644
--- a/plat/xilinx/common/ipi_mailbox_service/ipi_mailbox_svc.c
+++ b/plat/xilinx/common/ipi_mailbox_service/ipi_mailbox_svc.c
@@ -70,6 +70,9 @@
 			 uint64_t x3, uint64_t x4, const void *cookie,
 			 void *handle, uint64_t flags)
 {
+	(void) x4;
+	(void) flags;
+	(void) cookie;
 	int32_t ret;
 	uint32_t ipi_local_id;
 	uint32_t ipi_remote_id;
diff --git a/plat/xilinx/common/pm_service/pm_svc_main.c b/plat/xilinx/common/pm_service/pm_svc_main.c
index 193c5dc..861c5b3 100644
--- a/plat/xilinx/common/pm_service/pm_svc_main.c
+++ b/plat/xilinx/common/pm_service/pm_svc_main.c
@@ -79,6 +79,10 @@
 static uint64_t cpu_pwrdwn_req_handler(uint32_t id, uint32_t flags,
 				       void *handle, void *cookie)
 {
+	(void)id;
+	(void)flags;
+	(void)handle;
+	(void)cookie;
 	uint32_t cpu_id = plat_my_core_pos();
 
 	VERBOSE("Powering down CPU %d\n", cpu_id);
@@ -123,6 +127,9 @@
 static uint64_t ipi_fiq_handler(uint32_t id, uint32_t flags, void *handle,
 				void *cookie)
 {
+	(void)flags;
+	(void)handle;
+	(void)cookie;
 	uint32_t payload[4] = {0};
 	enum pm_ret_status ret;
 	int ipi_status, i;
@@ -546,6 +553,7 @@
 uint64_t pm_smc_handler(uint32_t smc_fid, uint64_t x1, uint64_t x2, uint64_t x3,
 			uint64_t x4, const void *cookie, void *handle, uint64_t flags)
 {
+	(void)cookie;
 	uintptr_t ret;
 	uint32_t pm_arg[PAYLOAD_ARG_CNT] = {0};
 	uint32_t security_flag = NON_SECURE_FLAG;