trivial: Add a simple style guide for firmware descriptions
trivial: Add a simple style guide for firmware descriptions

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