trivial: thunderbolt: If unable to find inactive nvmem, don't mark updatable
trivial: thunderbolt: If unable to find inactive nvmem, don't mark updatable

This situation may happen in the future in systems where the TBT NVM is embedded
in a different location and only upgradable through system firmware.

fwupd/fwupd,vathpela/fwupd,fwupd/fwupd,hughsie/fwupd,vathpela/fwupd,vathpela/fwupd,fwupd/fwupd,hughsie/fwupd,hughsie/fwupd,vathpela/fwupd,hughsie/fwupd,fwupd/fwupd