The best way of not getting something wrong is to not require it in the first
place...
All plugins now use DeviceInstanceId-style quirk matches and we can just drop
the prefix in all files. We were treating HwId=, Guid= and DeviceInstanceId= in
exactly the same way -- they're just converted to GUIDs when building the silo!
The DW5821e in modem mode uses the 0x81D7 PID, but when it boots in
fastboot mode it uses the 0x81D6 PID. The upgrade procedure was able
to automatically match these two devices because they both shared the
very generic per-VID (0x413C) GUID, but this is no longer operational
since commit 8ef139faba, as the very generic GUIDs have been removed
for matching purposes.
So, define a quirk for the DW5821e, in order to add a counterpart
GUID to make device matching work properly again.
Fixes https://github.com/hughsie/fwupd/issues/1271