Fix MISRA directive 4.7 warning (FreeRTOS#977)

Author: kar-rahul-aws

portable/Common/mpu_wrappers_v2.c

@@ -269,7 +269,7 @@
                 }
             }
         }
-        xTaskResumeAll();
+        ( void ) xTaskResumeAll();
 
         return lFreeIndex;
     }