drm/i915/rkl: Add new cdclk table

A recent bspec update has provided a new cdclk table for RKL.  All of
the cdclk values are the same as those we've been using on ICL, TGL,
etc., but we obtain them by doubling both the PLL ratio and CD2X divider
numbers.

Bspec: 49202
Cc: Anusha Srivatsa <anusha.srivatsa@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Anusha Srivatsa <anusha.srivatsa@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201015220038.271740-1-matthew.d.roper@intel.com