drm/i915/icl: Map VBT DDC Pin to BSpec DDC Pin

On ICL we need to map VBT DDC Pin to BSpec DDC Pin.
Adding ICL Pin Values.

According to VBT
Block 2 (General Bytes Definition)
DDC Bus

+----------+-----------+--------------------+
| DDI Type | VBT Value | BSpec Mapped Value |
+----------+-----------+--------------------+
| DDI-A    | 0x1       | 0x1                |
| DDI-B    | 0x2       | 0x2                |
| PORT-1   | 0x4       | 0x9                |
| PORT-2   | 0x5       | 0xA                |
| PORT-3   | 0x6       | 0xB                |
| PORT-4   | 0x7       | 0xC                |
+----------+-----------+--------------------+

Cc: James Ausmus <james.ausmus@intel.com>
Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Anusha Srivatsa <anusha.srivatsa@intel.com>
Cc: Clinton Taylor <clinton.a.taylor@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: James Ausmus <james.ausmus@intel.com>
Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
[Paulo: checkpatch fixes.]
Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180522002558.29262-9-paulo.r.zanoni@intel.com