plugins: modprobe: Support for coldplugging more devices
plugins: modprobe: Support for coldplugging more devices

As it turns out, not all buses in Linux will add `modalias` attributes
to their devices in sysfs. One notable exception are MDIO buses. The
plugin's scan routine would thus not pick them up.

Fortunately, the information is always available in the device's
`uevent` attribute.

Therefore, default to looking for modaliases in the device's `uevent`
attribute instead, falling back to `modalias` only if `uevent` is not
availble (this should never happen).

troglobit/finit,troglobit/finit