drm/i915/mtl: Dump C20 pll hw state

As we already do with C10 chip, let's dump the pll
hw state for C20 as well.

Reviewed-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Reviewed-by: Arun R Murthy <arun.r.murthy@intel.com>
Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230428095433.4109054-4-mika.kahola@intel.com