drm/i915: Relocate a few more pch transcoder bits

Move intel_crtc_pch_transcoder() and has_pch_trancoder() to a
more appropritate place (intel_pch_display.c).

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220221110356.5532-4-ville.syrjala@linux.intel.com


Reviewed-by: Jani Nikula <jani.nikula@intel.com>