In the case of vbt residing in opregion, we simply remap the region
into the kernel and pass the memory reference. Instead duplicate the
memory to handle a saner cleanup in intel_bios_init.

Cc: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240228213235.2495611-6-radhakrishna.sripada@intel.com