fix(plat/xilinx/versal): resolve misra R15.6 in pm services

MISRA Violation: MISRA-C:2012 R.15.6
- The body of an iteration-statement or a selection-statement shall be
  a compound statement

Signed-off-by: Abhyuday Godhasara <abhyuday.godhasara@xilinx.com>
Change-Id: I82e924a77ee3afeb56fa18714e94cc4f6fff5a49
diff --git a/plat/xilinx/versal/pm_service/pm_svc_main.c b/plat/xilinx/versal/pm_service/pm_svc_main.c
index 87ba732..6a79fc5 100644
--- a/plat/xilinx/versal/pm_service/pm_svc_main.c
+++ b/plat/xilinx/versal/pm_service/pm_svc_main.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2019-2020, Xilinx, Inc. All rights reserved.
+ * Copyright (c) 2019-2021, Xilinx, Inc. All rights reserved.
  *
  * SPDX-License-Identifier: BSD-3-Clause
  */
@@ -138,8 +138,9 @@
 	uint32_t security_flag = SECURE_FLAG;
 
 	/* Handle case where PM wasn't initialized properly */
-	if (!pm_up)
+	if (!pm_up) {
 		SMC_RET1(handle, SMC_UNK);
+	}
 
 	pm_arg[0] = (uint32_t)x1;
 	pm_arg[1] = (uint32_t)(x1 >> 32);