drm/gem: Properly annotate WW context on drm_gem_lock_reservations() error

Use ww_acquire_fini() in the error code paths. Otherwise lockdep
thinks that lock is held when lock's memory is freed after the
drm_gem_lock_reservations() error. The WW needs to be annotated
as "freed", which fixes the noisy "WARNING: held lock freed!" splat
of VirtIO-GPU driver with CONFIG_DEBUG_MUTEXES=y and enabled lockdep.

Cc: stable@vger.kernel.org
Signed-off-by: Dmitry Osipenko <dmitry.osipenko@collabora.com>