nouveau: pull in major libdrm rewrite

Redesigned primarily to allow us to better take advantage of BO's having
fixed GPU virtual addresses on GeForce 8 and up, and to reduce the overhead
of handling relocations on earlier chipsets.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Christoph Bumiller <e0425955@student.tuwien.ac.at>