drm/i915: do not map aperture if it is not available.

Skip both setup and cleanup of the aperture mapping if the HW doesn't
have an aperture bar.

Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20191029095856.25431-2-matthew.auld@intel.com
1 file changed