Let's enable the hardware hpd logic only for the ports we
can actually use.

In theory this may save some miniscule amounts of power,
and more importantly it eliminates a lot if platform specific
codepaths since the generic thing can now deal with any
combination of ports being present on each SKU.

v2: Deal with DG1
v3: Deal with DG1 some more
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201028213323.5423-18-ville.syrjala@linux.intel.comReviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>