staging/rdma/hfi1: Change send_schedule counter to a per cpu counter

A patch to fix fairness issues in QP scheduling requires
n_send_schedule counter to be converted to a per cpu counter to reduce
cache misses.

Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Vennila Megavannan <vennila.megavannan@intel.com>
Signed-off-by: Jubin John <jubin.john@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>