drm/i915: Suck snps/cx0 PLL states into dpll_hw_state

drm/i915: Suck snps/cx0 PLL states into dpll_hw_state

For some reason the snps/cx0 PLL states were added into
a union alongside dpll_hw_state. Just suck them into
dpll_hw_state so that we don't have so many levels of
unions/etc.

TODO: Get rid of 'clock' from the snps/cx0 PLL states
      as it is not a register values and thus doesn't
      belong there

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240412182703.19916-19-ville.syrjala@linux.intel.com
Reviewed-by: Jani Nikula <jani.nikula@intel.com>