udf: Implement searching for directory entry using new iteration code

[ Upstream commit 1c80afa0 ]

Implement searching for directory entry - udf_fiiter_find_entry() -
using new directory iteration code.

Reported-by:  <syzbot+69c9fdccc6dd08961d34@syzkaller.appspotmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@igalia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>