CVE-2025-21859

In the Linux kernel, the following vulnerability has been resolved:

USB: gadget: f_midi: f_midi_complete to call queue_work

When using USB MIDI, a lock is attempted to be acquired twice through a
re-entrant call to f_midi_transmit, causing a deadlock.

Fix it by using queue_work() to schedule the inner f_midi_transmit() via
a high priority work queue from the completion handler.