net/smc: Pass on DMBE bit mask in IRQ handler

Make the DMBE bits, which are passed on individually in ism_move() as
parameter idx, available to the receiver.

Signed-off-by: Stefan Raspl <raspl@linux.ibm.com>
Signed-off-by: Wenjia Zhang &lt; <wenjia@linux.ibm.com>
Reviewed-by: Tony Lu <tonylu@linux.alibaba.com>
Signed-off-by: David S. Miller <davem@davemloft.net>