trivial: dell create a function for looking up system ID
trivial: dell create a function for looking up system ID

Enough places look for it that code duplication should go away.

superm1/fwupd,hughsie/fwupd,fwupd/fwupd,hughsie/fwupd,superm1/fwupd,vathpela/fwupd,vathpela/fwupd,fwupd/fwupd,hughsie/fwupd,vathpela/fwupd,superm1/fwupd,fwupd/fwupd,fwupd/fwupd,vathpela/fwupd,hughsie/fwupd