drm/i915: Bump max TMDS bitrate to 6 Gbps on ADL-S/ADL-P/DG2+

Bspec lists the mas TMDS bitrate as 6 Gbps on ADL-S/ADL-P/DG2.
Bump our limit to match.

v2: Bump for ADL-S as well (Jani)

Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240520164732.3682-1-ville.syrjala@linux.intel.com


Reviewed-by: Jani Nikula <jani.nikula@intel.com>