staging/rdma/hfi1: Remove CQ data structures and functions from hfi1

The completion queue is not a complex data structure and it can be removed
at the same time as its functions. Unlike the more complicated queue pair
which was done in multiple patches. This single patch removes all traces
of hfi1 specific completeion queues from the hfi1 driver.

Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Harish Chegondi <harish.chegondi@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>