drm/i915: Use _PICK() for CHICKEN_TRANS()

Make CHICKEN_TRANS() a bit less special looking by using _PICK().

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20191024122138.25065-1-ville.syrjala@linux.intel.com


Reviewed-by: José Roberto de Souza <jose.souza@intel.com>