drm/xe/display: drop unused rawclk_freq and RUNTIME_INFO()

With rawclk_freq moved to display runtime info, xe has no users left for
them.

Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/9f09274bddc14f555c0102f37af6df23b4433102.1724144570.git.jani.nikula@intel.com


Signed-off-by: Jani Nikula <jani.nikula@intel.com>