In the case where we can trigger the replug automatically we can have to wait
for a USB re-enumeration (typically a few hundred ms) but when the user is
requred to unplug, and then replug we have to wait a bit longer.
The 'remove delay' allows us to modify per-device the removal delay. In the
case the device does not show back up in the correct time the device will be
auto-removed and the session will get a DeviceRemoved signal. In the case where
the device in bootloader mode shows up within the timeout the session just gets
a DeviceChanged event.
For the duration of the delayed removal the flags for the device are set to
zero to ensure the session does not try to interact with the device whilst
re-enumerating.
It's actually less scary to see a SHA1 hash than it is to see a path like
/sys/devices/pci0000:00/0000:00:1d.0/usb1/1-1/1-1.2. It's also way easier to
copy and paste into the various fwupdmgr command that require a device ID and
also means we can match a partial prefix much like git allows.
If we also move to a model where plugins can be changed during different stages
of the update (e.g. during detach) then the device might change connection type
and then the sysfs path not only becomes difficult to paste, but incorrect.
Session software doesn't care about the format of the device ID (it is supposed
to be an implementation detail) and so there's no API or ABI break here. A few
plugins also needed to be ported, but nothing too worrying.
Handling this in one place prevents plugins setting different values for
non-string values like TRUE/false or with different ways to represent integers.
For example, matching on the 'USB\VID_0000&PID_0000&REV_0000' GUID rather than
the 'USB\VID_0000&PID_0000' GUID.
This is now possible as we can specify multiple GUIDs for a device.
Allow devices to have a specific device ID, which also matches other equivalent
IDs from other providers
This allows the user to plug in one type of device, and not match a different
cached device that also matches the same provider.
