i915: Use arch_phys_wc_{add,del}

i915 open-coded logic that was essentially equivalent to the new API.

Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Dave Airlie <airlied@redhat.com>
1 file changed