gbmcweb: Add Redfish BootOption DELETE

Adds DELETE /redfish/v1/Systems/<id>/Boot/BootOptions/<ref>/ to remove a
UEFI boot option via SystemRegistry::DeleteBootOption.

- Returns 204 No Content on success, 404 if the boot option does not exist,
  and 500 for any other registry error.

Google-Bug-Id:539554519
PiperOrigin-RevId: 995317696
Change-Id: Ib65aa8a3f81d9f845b0bfd90616a7c09a6fdfedd
1 file changed