Post-commit fix for Bug#41158

A label statement needs to be followed by at least
one primary expression.  If built without
WITH_PARTITION_STORAGE_ENGINE set, the block would 
be empty.

Added ';' as a dummy statement to fix it.

sql/sql_table.cc

@@ -1783,6 +1783,7 @@ bool mysql_write_frm(ALTER_PARTITION_PARAM_TYPE *lpt, uint flags)
     part_info->frm_log_entry= NULL;
     (void) sync_ddl_log();
 #endif
+    ;
   }
 
 end: