drm/i915: Drop the cached per-pipe min_cdclk[] from bw state

drm/i915: Drop the cached per-pipe min_cdclk[] from bw state

intel_bw_crtc_min_cdclk() only depends on the pipe data rate,
which we already have stashed in bw_state->data_rate[]. So
stashing the resulting min_cdclk[] as well is redundant. Get
rid of it.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20250326162544.3642-2-ville.syrjala@linux.intel.com
Reviewed-by: Jani Nikula <jani.nikula@intel.com>