vc4: Fix referencing of sync objects.

While the pipe_reference_* helpers set the pointer, a bare pipe_reference
doesn't.   Fixes 5 ARB_sync tests.
r200: Avoid out of bounds array access.

Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
glapi: Make mapi/glapi/gen before mapi to avoid distcheck problem.
util: Add headers and python scripts for distribution.
configure.ac: Drop generating egl-static and gbm Makefiles.
glapi/gen: Add KHR_context_flush_control.xml to distribution.
dri/common: Drop unused mmio.h.

Unused since commit 7550a24f.
mapi: Add mapi_abi.py to EXTRA_DIST
vgapi: Add vgapi.csv to distribution.
dri/common: Add files to distribution.
mesa: Add python scripts to distribution.
glsl: Distribute tests/, TODO, and README
glsl: Add headers to distribution.
gtest: Add headers to distribution.
configure.ac: Use tar-ustar archive format.

The default tar-v7 archive format doesn't support filenames longer than
99 characters, of which we have a few (in src/glsl/tests/lower_jumps/).
configure.ac: Ship .xz compressed tarballs, in addition to .gz.

11 MiB -> 6.5 MiB.
include: Add remaining headers to distribution.
glsl: Add lex and yacc sources to distribution.

Since we have manual build rules and list the .c/.cpp files in SOURCES,
we need to explicitly list these for distribution.
mesa: Alphabetize MAIN_FILES.
mesa: Add headers to distribution.