drm/i915/mtl/display: Implement DisplayPort sequences

The differences between MTL and TGL DP sequences are big enough to
MTL have its own functions.

Also it is much easier to follow MTL sequences against spec with
its own functions.

One change worthy to mention is the move of
'intel_display_power_get(dev_priv, dig_port->ddi_io_power_domain)'.
This call is not necessary for MTL but we have _put() counter part in
intel_ddi_post_disable_dp() that needs to balanced.
We could add a display version check on it but instead here it is
moving it to intel_ddi_pre_enable_dp() so it is executed for all
platforms in a single place and this will not cause any harm in MTL
and newer platforms.

v2:
 - Fix logic to wait for buf idle.
 - Use the right register to wait for ddi active.(RK)
v3:
 - Increase wait timeout for ddi buf active (Mika)
v4:
 - Increase idle timeout for ddi buf idle (Mika)
v5: use rmw in mtl_disable_ddi_buf. Donot clear
    link training mask(Imre)

BSpec: 65448 65505
Cc: Matt Roper <matthew.d.roper@intel.com>
Cc: Satyeshwar Singh <satyeshwar.singh@intel.com>
Cc: Clint Taylor <clinton.a.taylor@intel.com>
Cc: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Cc: Imre Deak <imre.deak@intel.com>
Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230413212443.1504245-7-radhakrishna.sripada@intel.com