This is to help break the dependence on the Dell plugin during
initalization.
NOTE: there are corner cases that this plugin will no longer
detect Dell systems now, but these are expected to be rare.
Over the months the original meaning of ALLOW_OFFLINE and ALLOW_ONLINE have be
lost, and there is now a confusing mixture of uses in the source tree. With this
commit we make it clear the UPDATABLE flag is used to specify when the device is
updatable (e.g. from the desktop live session, or from the systemd offline
updates mode, or both) and the NEEDS_REBOOT flag lets us know when the update
is actually going to be done.
For instance, a UEFI UpdateCapsule can be *scheduled* from either the desktop
or from the update mode (but the latter would be a bit weird), but does require
a reboot. Some devices might only be updatable outside the live session, for
instance a hard drive update or a GPU update -- there's just too much going on
with a live session and we want to tightly control what's running during the
firmware flash.
This also means we don't have to "retry" the update when scheduling an update
that really can be scheduled whenever, but just requires a reboot to apply.
Although WD15 and TB16 share a same payload today, this may not
be the case some day in the future. Use the fu-dell-common method
to determine the dock in use to build the GUID.
There was a lot of confusion about when remote control was turned
on or off leading to dsyfunctional cascade support.
This has been confirmed to work for querying and flashing both
VMM3320s in a Rugged Latitude 5414 + dock.
The synapticsmst-common.c file had some global state so that cascade devices
could use the device fd. This made the control flow error prone, and it meant
that the fd could be leaked trivially on any error path.
Moving the fd ownership to the device is the logical place for the control, and
means we can create "connections" to access the main device and the cascade
devices.
This fixes the warnings detected by Coverity.
