drm/msm: gpu: Only sync fences on rings that exist

The fault recovery code tries to sync fences on all possible rings
instead of only the rings that actually exist which will fault the
kernel when the number of rings are less than the maximum amount.
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

drivers/gpu/drm/msm/msm_gpu.c

@@ -308,7 +308,7 @@ static void recover_worker(struct work_struct *work)
 	 * needs to happen after msm_rd_dump_submit() to ensure that the
 	 * bo's referenced by the offending submit are still around.
 	 */
-	for (i = 0; i < ARRAY_SIZE(gpu->rb); i++) {
+	for (i = 0; i < gpu->nr_rings; i++) {
 		struct msm_ringbuffer *ring = gpu->rb[i];
 
 		uint32_t fence = ring->memptrs->fence;