radio_si470x: Fix free memory corruption

The release path for a disconnected device frees the object then unlocks
the mutex in the freed object...

Found by Dan Carpenter using Smatch

Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 file changed