radio_si470x: Fix free memory corruption
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 <91e38e63b890fbb214c8914809fde03c73e7f24d@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <69652caca27c8b940640ad396ab71f93cacec34f@linux-foundation.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas