The find(1) -perm +mode is no longer supported and has been deprecated since
2005.

This could resolve #13855 ticket.

Signed-off-by: Rocco Folino <lordzen87@gmail.com>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@40927 3c298f89-4303-0410-b956-a3cf2f4a3e73