mostly fix amd64 xorg-server 1.20 builds:

- avoid bswap_16 etc defines for now. ends up with code-in-decl
- more ABI_VERSION 23 fixes (BlockHandler/WakeHandler) including re-fix
from previous
- more Notify API
- more shadowUpdatePackedWeak() removal
- remove fd_set handling from intel driver (part of ABI_VERSION 23)
- cope better with PixMap/Drawable separation in new server
- remove support for maxHValue and maxVValue (XXX?)
- hide drmmode_udev_notify() when not building udev
- comment out nouveau 'wfb' support, xorg-server 1.20 only supplies
either 'wfb' or 'fb' interface, not both, and we choose 'fb'
- define 'pointer' in nv_proto.h rather than relying upon Xdefs.h
- normalise the value of _XTYPEDEF_POINTER
- EGL is broken (missing) in xsrc currently

merge xf86-video-geode 2.11.18, xf86-video-openchrome 0.4.0,
xf86-video-rendition 4.2.6, and xf86-video-s3virge 1.10.7.

mibstore.h and its miInitializeBackingStore() have been otherwise empty
since at least xorg-server 1.10. remove all reference to them as the
header is gone in xorg-server 1.18.

initial import of xf86-video-rendition-4.2.5

initial import of xf86-video-rendition-4.2.3

initial import of xf86-video-rendition-4.2.2

initial import of xf86-video-rendition-4.2.1

initial import of xf86-video-rendition-4.1.3