Remove the FuDeviceClass padding, as this library now loaded using an rpath
rather than a shared library with a static API. This matches what we did for
the FuFirmwareClass objects a while ago.
Now two plugins are using hardcoded SPI constants for various CFI chips,
and it makes sense to have some common quirk data that can be used by
both.
Add a FuSpiChip helper object that can be used by FuDevice subclasses
to get the specific SPI commands to use for each flash ID.