(partially) Fix Bug#55227 Fix compiler warnings in innodb with gcc 4.6

Fix compiler warning:
que/que0que.c: In function 'que_run_threads_low':
que/que0que.c:1287:9: error: variable 'cumul_resource' set but not used [-Werror=unused-but-set-variable]

storage/innodb_plugin/que/que0que.c

@@ -1284,18 +1284,13 @@ que_run_threads_low(
 	que_thr_t*	thr)	/*!< in: query thread */
 {
 	que_thr_t*	next_thr;
-	ulint		cumul_resource;
 	ulint		loop_count;
 
 	ut_ad(thr->state == QUE_THR_RUNNING);
 	ut_a(thr_get_trx(thr)->error_state == DB_SUCCESS);
 	ut_ad(!mutex_own(&kernel_mutex));
 
-	/* cumul_resource counts how much resources the OS thread (NOT the
-	query thread) has spent in this function */
-
 	loop_count = QUE_MAX_LOOPS_WITHOUT_CHECK;
-	cumul_resource = 0;
 loop:
 	/* Check that there is enough space in the log to accommodate
 	possible log entries by this query step; if the operation can touch