stun: close socket before returning in error case

Do not leak the socket resource when bailing out in error case.

Found by the coverty scanner.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
cpus: let it always return an unsigned int and bail out on error

In case of an error, just panic, to make sure we always get a val >= 1.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>