xf86-video-sis: Changes to 'master'

[Jeremy Huddleston]

Rebased ref, commits from common ancestor:
commit 06f8213bffd27360d5cc3df0cad19b102cc928e2
Author: Jeremy Huddleston <jeremyhu at apple.com>
Date:   Sat Oct 29 17:32:21 2011 -0700

    pciTag was removed from xorg-server, so provide it in-driver until this is updated to use libpciaccess
    
    Signed-off-by: Jeremy Huddleston <jeremyhu at apple.com>