drm/i915: HDCP support on above PORT_E

As Gen12 onwards there are HDCP instances for each transcoder
instead of port, remove the (port < PORT_E) hdcp support
limitation for platform >= Gen12.

v2:
 - Nuke the comment and cosmetic changes. [Jani]

Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Ramalingam C <ramalingam.c@intel.com>
Reviewed-by: Ramalingam C <ramalingam.c@intel.com>
Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200207144116.20172-1-anshuman.gupta@intel.com