A subset of 71724f70 ("drm/mm: Use helpers for drm_mm_node booleans")
in order to prepare drm-intel-next-queued for subsequent patches before
we can backmerge 71724f70 itself.
Signed-off-by: NChris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: NTvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191004142226.13711-1-chris@chris-wilson.co.uk