This allows us to set the subsystem and device file during construction, which
means we can create FuUdevDevice objects not backed by physical devices.
It wasn't hugely clear what the platform ID was actually meant to represent. In
some cases it was being used like a physical ID, in others it was a logical ID,
and in others it was both. In some cases it was even used as a sysfs path.
Clear up all the confusion by splitting the platform ID into two parts, an
optional *physical* ID to represent the electrical connection, and an optional
*logical* ID to disambiguate composite devices with the same physical ID.
Also create an explicit sysfs_path getter for FuUdevDevice to make this clear.
This allows WAIT_FOR_REPLUG to always work, rather than depending on the order
that the GUIDs were added, and that the kernel would always return the same
sysfs path (which it doesn't have to do, especially for hidraw devices).
The daemon creates a baseclass of either FuUsbDevice or FuUdevDevice when the
devices are added or coldplugged to match the quirk database and to find out
what plugin to run.
This is proxied to plugins, but they are given the GUsbDevice or GUdevDevice and
the FuDevice is just thrown away. Most plugins either use a FuUsbDevice or
superclassed version like FuNvmeDevice and so we re-create the FuDevice, re-probe
the hardware, re-query the quirk database and then return this to the daemon.
In some cases, plugins actually probe the hardware three times (!) by creating
a FuUsbDevice to get the quirks, so that the plugin knows what kind of
superclass to create, which then itself probes the hardware again.
Passing the temporary FuDevice to the plugins means that the simplest ones can
just fu_plugin_device_add() the passed in object, or create a superclass and
incorporate the actual GUsbDevice and all the GUIDs.
This breaks internal plugin API but speeds up startup substantially and deletes
a lot of code.
Objects deriving from FuUdevDevice() like FuNvmeDevice typically want to do
FuDevice->FuUdevDevice->FuNvmeDevice rather than FuDevice->FuNvmeDevice.
This matches what FuUsbDevice does.
There are currently three plugins that use GUdev rather than libusb, and there
are several more in the works. Add a helper object so we can make the plugins
smaller and simpler, much like we already do with FuUsbDevice.