If incorporating the version from a subclass, also set the verfmt too
If incorporating the version from a subclass, also set the verfmt too

Otherwise we could be left with a device that sets the expected verfmt in the
plugin _init(), but would not be inherited from the subclass. It would have:

    Version:              0.2
    VersionFormat:        triplet

...which makes no sense.

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