gfs2: Don't set GLF_LOCK in gfs2_dispose_glock_lru

In gfs2_dispose_glock_lru(), we want to skip glocks which are in the
process of transitioning state (as indicated by the set GLF_LOCK flag),
but we we don't need to set that flag for requesting a state transition.
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>

fs/gfs2/glock.c

@@ -2017,14 +2017,13 @@ __acquires(&lru_lock)
 			atomic_inc(&lru_count);
 			continue;
 		}
-		if (test_and_set_bit(GLF_LOCK, &gl->gl_flags)) {
+		if (test_bit(GLF_LOCK, &gl->gl_flags)) {
 			spin_unlock(&gl->gl_lockref.lock);
 			goto add_back_to_lru;
 		}
 		gl->gl_lockref.count++;
 		if (demote_ok(gl))
 			handle_callback(gl, LM_ST_UNLOCKED, 0, false);
-		WARN_ON(!test_and_clear_bit(GLF_LOCK, &gl->gl_flags));
 		__gfs2_glock_queue_work(gl, 0);
 		spin_unlock(&gl->gl_lockref.lock);
 		cond_resched_lock(&lru_lock);