drm/i915: Remove mostly duplicated video DIP handling from PSR code

Now that the infoframe hooks are part of the intel_dig_port, we can use
the normal .write_infoframe() hook to update the VSC SDP. We do need to
deal with the size difference between the VSC DIP and the others though.

Another minor snag is that the compiler will complain to use if we keep
using enum hdmi_infoframe_type type and passing in the DP define instead,
so et's just change to unsigned int all over for the inforframe type.

v2: Rebase due to other PSR changes

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171013194051.19286-1-ville.syrjala@linux.intel.com