staging/rdma/hfi1: Implement hfi1 support for AH notification

For OPA devices additional work is required to create an AH.
This patch adds support to set the VL correctly.

Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>