glx: Update glxext.h to revision 24777.

It readds the GLXContextID typedef, but under #ifndef GLX_VERSION_1_3.

Bugzilla: https://cvs.khronos.org/bugzilla/show_bug.cgi?id=11454

(Backported from commit 3f3aafbfeeb3939cb5cf710954ccefb8bbe9cff9)
mesa: Fix build to properly check for supported compiler flags

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=72708
Reviewed-by: Matt Turner <mattst88@gmail.com>
Signed-off-by: Lauri Kasanen <cand@gmx.com>
(cherry picked from commit fcefdc9a595c52ade2be15e0f3a2f301fee3599c)
build: move ARCH_LIBS definition outside of ASM definition

_mesa_streaming_load_memcpy is also needed even if assembling is disabled

Cc: "10.0" <mesa-stable@lists.freedesktop.org>
Reviewed-by: Matt Turner <mattst88@gmail.com>
(cherry picked from commit 1cdeeef6c400979a0497afde52bf351a623a934f)
Update version to 10.0.3

In preparation for the upcoming 10.0.3 release.
docs: Add release notes for 10.0.3 release.

Just before making the actual release.
docs: Add md5sums for 10.0.3 release

Which we couldn't do until after tagging the release, of course.