s3:smbd: add negprot remote arch detection for OSX

s3:smbd: add negprot remote arch detection for OSX

Remote arch detection for OSX clients has been broken for some time, since
both Samba and OSX started supporting SMB2.  Fix it by adding modern OSX
client detection support to the negprot remote arch detection routine.

Signed-off-by: Justin Maggard <jmaggard10@gmail.com>
Reviewed-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Ralph Boehme <rb@sernet.de>
Autobuild-User(master): Jeremy Allison <jra@samba.org>
Autobuild-Date(master): Thu Mar  3 09:03:53 CET 2016 on sn-devel-144

(cherry picked from commit d7ca174744001fabdc32e1c334dad347bb985756)

Autobuild-User(v4-2-test): Karolin Seeger <kseeger@samba.org>
Autobuild-Date(v4-2-test): Mon Mar 14 15:26:25 CET 2016 on sn-devel-104