fuse: fix fuse_file_lseek returning with lock held

This bug was found with smatch (http://repo.or.cz/w/smatch.git/).  If
we return directly the inode->i_mutex lock doesn't get released.
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@kernel.org

fs/fuse/file.c

@@ -1465,7 +1465,7 @@ static loff_t fuse_file_llseek(struct file *file, loff_t offset, int origin)
 	case SEEK_END:
 		retval = fuse_update_attributes(inode, NULL, file, NULL);
 		if (retval)
-			return retval;
+			goto exit;
 		offset += i_size_read(inode);
 		break;
 	case SEEK_CUR:
@@ -1479,6 +1479,7 @@ static loff_t fuse_file_llseek(struct file *file, loff_t offset, int origin)
 		}
 		retval = offset;
 	}
+exit:
 	mutex_unlock(&inode->i_mutex);
 	return retval;
 }