i965: Import libdrm_intel.

i965: Import libdrm_intel.

This imports commit 19c4cfc54918d361f2535aec16650e9f0be667cd of
libdrm/intel/*.[ch], minus a few files that we're never going to use
(and would immediately delete), plus a few necessary dependencies.

We rename intel_bufmgr.h to brw_bufmgr.h to avoid #include conflicts.
We also fix UTF-8 symbol problems in intel_bufmgr_gem.c comments
because vim keeps trying to fix that every time I edit the file,
and we may as well fix it right away.

Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Jason Ekstrand <jason@jlekstrand.net>