drm/nouveau: bump version to 1.0.0

The time has come to get a proper version number that we can change to
indicate new features etc, rather than the lock-step 0.0.XX that we
previously had.

libdrm has recognised this version as compatible with 0.0.16 since 2.4.22,
so hopefully any breakage people see should be very minimal.

Signed-off-by: Ben Skeggs <bskeggs@redhat.com>