drm/i915: Pass dev_priv to skl_init_scalers()

Unify our approach to things by passing around dev_priv instead of dev.
While at it let's do some house cleaning: s/intel_foo/foo/ and move
things into tighter scope.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477946245-14134-3-git-send-email-ville.syrjala@linux.intel.com


Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>