drm/i915/dvo/ns2501: Nuke pointless casts

The dvo 'dev_priv' is void* so no need for an explicit cast.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240208151720.7866-13-ville.syrjala@linux.intel.com


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