typo fixed

sql/sql_cache.cc

@@ -305,7 +305,7 @@ TODO list:
 #define RW_RLOCK(M) {DBUG_PRINT("lock", ("rwlock rlock 0x%lx", (ulong)(M))); \
   if (!rw_rdlock(M)) DBUG_PRINT("lock", ("rwlock rlock ok")) \
   else DBUG_PRINT("lock", ("rwlock wlock FAILED %d", errno)); }
-#define RW_UNLOCK(M) {DBUG_PRINT("lock", ("rwlock wlock 0x%lx",(ulong)(M))); \
+#define RW_UNLOCK(M) {DBUG_PRINT("lock", ("rwlock unlock 0x%lx",(ulong)(M))); \
   if (!rw_unlock(M)) DBUG_PRINT("lock", ("rwlock unlock ok")) \
   else DBUG_PRINT("lock", ("rwlock unlock FAILED %d", errno)); }
 #define STRUCT_LOCK(M) {DBUG_PRINT("lock", ("%d struct lock...",__LINE__)); \