drm/i915: For HPD connected port use hpd_pin instead of port.

drm/i915: For HPD connected port use hpd_pin instead of port.

Let's try to simplify this mapping to hpd_pin -> bit
instead using port.
So for CNL with port F where we have this port using
hdp_pin and bits of other ports we don't need to duplicated
the mapping.

But for now this is only a re-org with no functional change
expected.

v2: Add missing lines and nuke @port reference from code
    documentation. (Ville)

Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Suggested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180129232223.766-7-rodrigo.vivi@intel.com