drm/i915: Move ddi_pll_sel into the pipe config

Just boring sed job for preparation.

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
[imre: rebased on patchset version w/o pch/crt/fdi refactoring]
Signed-off-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>