net/smc: multi-link support for smc_rmb_rtoken_handling()

Extend smc_rmb_rtoken_handling() and smc_rtoken_delete() to support
multiple links.

Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Reviewed-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>