ALSA: rawmidi: Fix kvfree() call in spinlock

ALSA: rawmidi: Fix kvfree() call in spinlock

commit 20c0c49720dc4e205d4c1d64add56a5043c5ec5f upstream.

At the conversion of locking with guard(), I overlooked that kvfree()
must not be called inside the spinlock unlike kfree(), and this was
caught by syzkaller now.

This patch reverts the conversion partially for restoring the kvfree()
call outside the spinlock.  It's not trivial to use guard() in this
context, unfortunately.

Fixes: 84bb065b316e ("ALSA: rawmidi: Use guard() for locking")
Reported-by: syzbot+351f8764833934c68836@syzkaller.appspotmail.com
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Closes: https://lore.kernel.org/6744737b.050a0220.1cc393.007e.GAE@google.com
Cc: <stable@vger.kernel.org>
Link: https://patch.msgid.link/20241125142041.16578-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>