We use the ParentGuid quirk key to logically 'tie-together' different discrete
devices into one logical device, for instance making the USB soundcard in a hub
the child of the USB controller on the same PCB.
Setting the discrete child is sometimes correct, for instance when rebooting
the hub, the audio device also goes away -- but it's also sometimes wrong.
If we set the child for a discrete device and the parent does *not* go away
then we get to a situation where the child reference may no longer be valid
if it comes back as a different object.
When we try to remove this no-longer-valid device with the removal timeout the
daemon segfaults. This is realy bad.
Continue to allow using fu_device_add_child() in plugins, where we know the
child lifecycle is is matched by the the parent. In the engine just set the
parent ID directly and let the client use this information to show the tree of
logical devices correctly. There's no benefit to setting up the children as
referenced objects anyway.
Sometimes plugins need to retry various commands send to hardware, either due
to unreliable transfers (e.g. using USB bulk) or from slightly quirky hardware.
Between them they seem to get various things wrong; either the error messages
are repeated and thus difficult to parse, or they just get the memory handling
of `g_propagate_prefixed_error()` wrong.
Providing sane helpers we can reduce the amount of boilerplate. Additionally
we can support a 'reset' function that can try to automatically recover the
hardware for specific error domains and codes.
Sometimes we only want to add the instance ID to get the quirk matches, and it
is confusing to see the "fake" IDs in the 'fwupdmgr get-devices' output.
If the measurements are missing but it's a UEFI system, it's a good indication
that the user has secure boot turned off.
Notify the user on the UEFI device through a non-fatal `UpdateMessage`
To accomplish this, move fu-uefi-vars into the plugin library for other plugins to use
If we say that the version format should be the same for the `version_lowest`
and the `version_bootloader` then it does not always make sense to set it at
the same time.
Moving the `version_format` to a standalone first-class property also means it
can be typically be set in the custom device `_init()` function, which means we
don't need to worry about *changing* ther version format as set by the USB and
UDev superclass helpers.
