fix(zynqmp): resolve misra R15.7 warnings

MISRA Violation: MISRA-C:2012 R.15.7
- All if . . else if constructs shall be terminated
with an else statement.

Signed-off-by: Venkatesh Yadav Abbarapu <venkatesh.abbarapu@xilinx.com>
Change-Id: If921ca7c30b2feea6535791aa15f4de7101c3134
diff --git a/plat/xilinx/common/ipi.c b/plat/xilinx/common/ipi.c
index 453e0b5..2f52f38 100644
--- a/plat/xilinx/common/ipi.c
+++ b/plat/xilinx/common/ipi.c
@@ -95,6 +95,8 @@
 		ret = -EPERM;
 	} else if (IPI_IS_SECURE(remote) && !is_secure) {
 		ret = -EPERM;
+	} else {
+		/* To fix the misra 15.7 warning */
 	}
 
 	return ret;