raid5: revert commit 11367799f3d1

Revert commit 11367799f3d1 ("md: Prevent IO hold during accessing to faulty
raid5 array") as it doesn't comply with commit c3cce6cda162 ("md/raid5:
ensure device failure recorded before write request returns."). That change
is not required anymore as the problem is resolved by commit 16f889499a52
("md: report 'write_pending' state when array in sync") - read request is
stuck as array state is not reported correctly via sysfs attribute.

Signed-off-by: Tomasz Majchrzak <tomasz.majchrzak@intel.com>
Signed-off-by: Shaohua Li <shli@fb.com>

drivers/md/raid5.c

@@ -4645,9 +4645,7 @@ finish:
 	}
 
 	if (!bio_list_empty(&s.return_bi)) {
-		if (test_bit(MD_CHANGE_PENDING, &conf->mddev->flags) &&
-				(s.failed <= conf->max_degraded ||
-					conf->mddev->external == 0)) {
+		if (test_bit(MD_CHANGE_PENDING, &conf->mddev->flags)) {
 			spin_lock_irq(&conf->device_lock);
 			bio_list_merge(&conf->return_bi, &s.return_bi);
 			spin_unlock_irq(&conf->device_lock);