drm/i915/tgl: Add dkl phy programming sequences

Added DKL Phy sequences and helpers functions to program voltage
swing, clock gating and dp mode.

It is not written in DP enabling sequence but "PHY Clockgating
programming" states that clock gating should be enabled after the
link training but doing so causes all the following trainings to fail
so not enabling it for.

v2:
Setting the right HIP_INDEX_REG bits (José)

v3:
Adding the meaning of each column of tgl_dkl_phy_ddi_translations
Adding if gen >= 12 on intel_ddi_hdmi_level() and
intel_ddi_pre_enable_hdmi() instead of reuse part of gen >= 11 if

v4:
Moved the DP_MODE lane programing to another patch as ICL also
needed it
Sharing icl_phy_set_clock_gating() and icl_program_mg_dp_mode() with
TGL as bits and programing as now it almost identical to ICL

BSpec: 49292
BSpec: 49190

Cc: Imre Deak <imre.deak@intel.com>
Cc: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Imre Deak <imre.deak@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Clinton A Taylor <clinton.a.taylor@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190926210659.56317-2-jose.souza@intel.com