net/smc: add receive timeout check

The SMC receive function currently lacks a timeout check under the
condition that no data were received and no data are available. This
patch adds such a check.

Signed-off-by: Hans Wippel <hwippel@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>