samba: update to 3.6.22.

Samba 3.6.22 have been issued as security releases in order
to address CVE-2013-4408 (DCE-RPC fragment length field is incorrectly checked)
and CVE-2012-6150 (pam_winbind login without require_membership_of
restrictions).
Merge branch 'master' into next
Merge branch 'next' of ssh://git.ipfire.org/pub/git/ipfire-2.x into next