ext4: add blk_finish_plug in error case of writepages.

blk_finish_plug is needed in error case of writepages.

Signed-off-by: Namjae Jeon <linkinjeon@gmail.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>

fs/ext4/inode.c

@@ -2270,6 +2270,7 @@ retry:
 			ext4_msg(inode->i_sb, KERN_CRIT, "%s: jbd2_start: "
 			       "%ld pages, ino %lu; err %d", __func__,
 				wbc->nr_to_write, inode->i_ino, ret);
+			blk_finish_plug(&plug);
 			goto out_writepages;
 		}