staging/rdma/hfi1: Use rdmavt pkey verbs function

No need to keep providing the query pkey function. This is now being
done in rdmavt. Remove support from hfi1. The allocation and
maintenance of the list still resides in the driver.

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>