drm/i915/hdcp: Enable HDCP 1.4 and 2.2 on Gen12+

>From Gen12 onwards, HDCP HW block is implemented within transcoders.
Till Gen11 HDCP HW block was part of DDI.

Hence required changes in HW programming is handled here.

As ME FW needs the transcoder detail on which HDCP is enabled
on Gen12+ platform, we are populating the detail in hdcp_port_data.

v2:
  _MMIO_TRANS is used [Lucas and Daniel]
  platform check is moved into the caller [Lucas]
v3:
  platform check is moved into a macro [Shashank]
v4:
  Few optimizations in the coding [Shashank]
v5:
  Fixed alignment in macro definition in i915_reg.h [Shashank]
  unused variables "reg" is removed.
v6:
  Configuring the transcoder at compute_config.
  transcoder is used instead of pipe in macros.
  Rebased.
v7:
  transcoder is cached at intel_hdcp
  hdcp_port_data is configured with transcoder index asper ME FW.
v8:
  s/trans/cpu_transcoder
  s/tc/cpu_transcoder
v9:
  rep_ctl is prepared for TCD too.
  return moved into deault of rep_ctl prepare function [Shashank]

Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
Reviewed-by: Shashank Sharma <shashank.sharma@intel.com>
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Uma Shankar <uma.shankar@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190828164216.405-7-ramalingam.c@intel.com