postpone __putname() until after do_last()

Since do_last() doesn't mangle nd->last_name, we can safely postpone
__putname() done in handling of trailing symlinks until after the
call of do_last()
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>

fs/namei.c

@@ -1923,9 +1923,9 @@ struct file *do_filp_open(int dfd, const char *pathname,
 	mutex_lock(&dir->d_inode->i_mutex);
 	path.dentry = lookup_hash(&nd);
 	path.mnt = nd.path.mnt;
-	__putname(nd.last.name);
 	filp = do_last(&nd, &path, open_flag, flag, acc_mode, mode,
 		       pathname, dir, &is_link);
+	__putname(nd.last.name);
 	if (is_link)
 		goto do_link;
 	if (nd.root.mnt)