msm: kgsl: fix error handling in adreno_waittimestamp()

This function was incorrectly reporting hangs when an
error such as ERESTARTSYS was returned by
__wait_event_interruptible_timeout().

Change-Id: I9139b03c4b417d135663729c763343382328da77
CRs-Fixed: 321490
Signed-off-by: Jeremy Gebben <jgebben@codeaurora.org>
diff --git a/drivers/gpu/msm/adreno.c b/drivers/gpu/msm/adreno.c
index 12e093b..23ecfb3 100644
--- a/drivers/gpu/msm/adreno.c
+++ b/drivers/gpu/msm/adreno.c
@@ -1132,9 +1132,14 @@
 			mutex_lock(&device->mutex);
 
 			if (status > 0) {
+				/*completed before the wait finished */
 				status = 0;
 				goto done;
+			} else if (status < 0) {
+				/*an error occurred*/
+				goto done;
 			}
+			/*this wait timed out*/
 		}
 	}
 	if (!kgsl_check_timestamp(device, timestamp)) {