[PATCH 2/3] nvmet-rdma: use srq pointer in rdma_cmd

[Sagi Grimberg]

> This is a preparetion patch that creates an infrastructure in post
> recv mechanism for the SRQ per completion vector feature.
> 
> Change-Id: I0b0130920580e6999f0517400a45a1078e9553c9

No need for this Change-Id...