drm/i915/bios: Switch to kms debugs

The VBT code is all about displays, so switch to UT_KMS debugs
from UT_DRIVER.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240208151720.7866-7-ville.syrjala@linux.intel.com


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