drm/i915/xelpd: Handle new location of outputs D and E

drm/i915/xelpd: Handle new location of outputs D and E

The DDI naming template for display version 12 went A-C, TC1-TC6.  With
XE_LPD, that naming scheme for DDI's has now changed to A-E, TC1-TC4.

The XE_LPD design keeps the register offsets and bitfields relating to
the TC outputs in the same location they were previously.  The new "D"
and "E" outputs now take the locations that were previously used by TC5
and TC6 outputs, or what we would have considered to be outputs "H" and
"I" under the legacy lettering scheme.

For the most part everything will just work as long as we initialize the
output with the proper 'enum port' value.  However we do need to take
care to pick the correct AUX channel when parsing the VBT (e.g., a
reference to 'AUX D' is actually asking us to use the 8th aux channel,
not the fourth).  We should also make sure that our encoders and aux
channels are named appropriately so that it's easier to correlate driver
debug messages with the bspec instructions.

v2:
 - Update handling of TGL_TRANS_CLK_SEL_PORT.  (Jose)

v3:
 - Add hpd_pin to handle outputs D and E (Jose)
 - Fixed conversion of BIOS port to aux ch for TC ports (Jose)

Cc: José Roberto de Souza <jose.souza@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210514153711.2359617-2-matthew.d.roper@intel.com