drm/i915: Move DG2 tuning to the right function

Use gt_tuning_settings() for the recommended tunings rather than the one
for workarounds.

Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230306204954.753739-2-lucas.demarchi@intel.com