be friendly to macro expansion (#6101)

include/rtdef.h

@@ -61,9 +61,9 @@ extern "C" {
 /**@{*/
 
 /* RT-Thread version information */
-#define RT_VERSION                      4L              /**< major version number */
-#define RT_SUBVERSION                   1L              /**< minor version number */
-#define RT_REVISION                     1L              /**< revise version number */
+#define RT_VERSION                      4               /**< major version number */
+#define RT_SUBVERSION                   1               /**< minor version number */
+#define RT_REVISION                     1               /**< revise version number */
 
 /* RT-Thread version */
 #define RTTHREAD_VERSION                ((RT_VERSION * 10000) + \