Log Message:
Update to Mesa-7.0.4 (the head of the 7.0 branch in GIT).  Basically,
lots of bug fixes; the intent of my update was mostly to fix
problems with i915 and r300 dri drivers and to provide the best environment
possible for the xorg server update to the 1.4 branch.

Morever, many of our patches from pkgsrc, i.e. those removed in this commit,
are now included upstream.

Additionally, MesaDemos now builds.

NOTES:

 - MesaLib now requires xf86driproto 2.0.4, as earlier versions install
   dri_interface.h, which is not correct.

 - glu now exports its symbols via libtool's -export-symfile.
   The symfile is generated pre-build--see glu/Makefile.

 - glxinfo/glxgears do not seem to need to be linked to libpthread, and this
   seems to cause problems on NetBSD with the new drm code.  If I am wrong
   about this, please let me know.  The only program that seems to need
   libpthread is glthreads in MesaDemos.