CVE-2022-49772 ALSA: usb-audio: Drop snd_BUG_ON() from snd_usbmidi_output_open()

In the Linux kernel, the following vulnerability has been resolved: ALSA: usb-audio: Drop sndBUGON from sndusbmidioutputopen sndusbmidioutputopen has a check of the NULL port with sndBUGON. sndBUGON was used as this shouldn't have happened, but in reality, the NULL port may be seen when the devic...