liquidio: change octnic_ctrl_pkt to do synchronous soft commands

1. Change struct octnic_ctrl_pkt to support synchronous operation.
2. Change code which use structure octnic_ctrl_pkt to send sc's
   synchronously.

Signed-off-by: Weilin Chang <weilin.chang@cavium.com>
Signed-off-by: Felix Manlunas <felix.manlunas@cavium.com>
Signed-off-by: David S. Miller <davem@davemloft.net>