IB/umad: fix memory leaks

Don't leak packet if it had a timeout, and don't leak timeout struct
if queue_packet() fails.

Signed-off-by: Jack Morgenstein <jackm@mellanox.co.il>
Signed-off-by: Michael S. Tsirkin <mst@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>