drm/i915/tgl: Add gmbus gpio pin to port mapping

Add default GPIO pin mapping for all ports. Tiger Lake has 3 combophy
ports and 6 TC ports, gpio pin1-3 are mapped to combophy & pin9-14 are
mapped to TC ports.

Cc: Anusha Srivatsa <anusha.srivatsa@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Mahesh Kumar <mahesh1.kumar@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: José Roberto de Souza <jose.souza@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190711173115.28296-18-lucas.demarchi@intel.com