fix(xilinx): resolve misra rule 10.1 violations

Fixed below MISRA violation:
- MISRA Violation: MISRA-C:2012 R.10.1:
  - Operands shall not be of an inappropriate essential type.
- Fix:
  - Made operands of the same type.

Change-Id: I30a01cc0938603defba7572e9f4dd9ebe6d74a9c
Signed-off-by: Devanshi Chauhan Alpeshbhai <devanshi.chauhanalpeshbhai@amd.com>
diff --git a/plat/xilinx/common/include/pm_defs.h b/plat/xilinx/common/include/pm_defs.h
index 2d2ae64..462c60d 100644
--- a/plat/xilinx/common/include/pm_defs.h
+++ b/plat/xilinx/common/include/pm_defs.h
@@ -224,21 +224,21 @@
  *                           supported.
  */
 enum pm_ret_status {
-	PM_RET_SUCCESS,
-	PM_RET_ERROR_ARGS = 1,
-	PM_RET_ERROR_NOTSUPPORTED = 4,
-	PM_RET_ERROR_IOCTL_NOT_SUPPORTED = 19,
-	PM_RET_ERROR_INVALID_CRC = 301,
-	PM_RET_ERROR_NOT_ENABLED = 29,
-	PM_RET_ERROR_INTERNAL = 2000,
-	PM_RET_ERROR_CONFLICT = 2001,
-	PM_RET_ERROR_ACCESS = 2002,
-	PM_RET_ERROR_INVALID_NODE = 2003,
-	PM_RET_ERROR_DOUBLE_REQ = 2004,
-	PM_RET_ERROR_ABORT_SUSPEND = 2005,
-	PM_RET_ERROR_TIMEOUT = 2006,
-	PM_RET_ERROR_NODE_USED = 2007,
-	PM_RET_ERROR_NO_FEATURE = 2008
+	PM_RET_SUCCESS = 0U,
+	PM_RET_ERROR_ARGS = 1U,
+	PM_RET_ERROR_NOTSUPPORTED = 4U,
+	PM_RET_ERROR_IOCTL_NOT_SUPPORTED = 19U,
+	PM_RET_ERROR_NOT_ENABLED = 29U,
+	PM_RET_ERROR_INVALID_CRC = 301U,
+	PM_RET_ERROR_INTERNAL = 2000U,
+	PM_RET_ERROR_CONFLICT = 2001U,
+	PM_RET_ERROR_ACCESS = 2002U,
+	PM_RET_ERROR_INVALID_NODE = 2003U,
+	PM_RET_ERROR_DOUBLE_REQ = 2004U,
+	PM_RET_ERROR_ABORT_SUSPEND = 2005U,
+	PM_RET_ERROR_TIMEOUT = 2006U,
+	PM_RET_ERROR_NODE_USED = 2007U,
+	PM_RET_ERROR_NO_FEATURE = 2008U
 };
 
 /*