Guido Gunther authored Apr 22, 2021 and Guido Gunther committed Apr 26, 2021

The current logic was fragile and failed e.g. when the
FEEDBACKD_UDEV_VAL_LED would not match leaking the dev since the
g_object_unref() at the end of the loop was never hit.

Prevent that with automatic cleanup and explicitly ref'ing the
devs we want to use.