drm/i915: use transcoder select bits on VGA and HDMI on CPT

Required for 3 pipe functionality.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Tested-By: Eugeni Dodonov <eugeni.dodonov@intel.com>
Reviewed-By: Eugeni Dodonov <eugeni.dodonov@intel.com>
Signed-off-by: Keith Packard <keithp@keithp.com>

diff --cc drivers/gpu/drm/i915/intel_crt.c
Simple merge

diff --cc drivers/gpu/drm/i915/intel_hdmi.c
Simple merge