[Mesa-stable] Stable 10.0 branch updated for imminent release

[Matt Turner]

We definitely want to apply "glx: Update glxext.h to revision 24777."
in time for the next 10.0 release. It fixes a really annoying problem
with the GL headers that make distributions lives awful. I sent this
to mesa-stable@ on the 25th. It's a slightly different than what's on
master due to some other patches being applied to one branch but not
the other.