IB/hfi1: Fix QOS num_vl bit width

The bit width for num_vls, n, needs to be calculated based on
the pow2 rounded up of the number of vls.  Otherwise num_vls of 3,
5, 6, and 7 will have misplaced QOS RSM map entries.

Reviewed-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>