staging/hfi1: Fix Xmit Wait calculation

Total XMIT wait needs to sum the xmit wait values of all the VLs not just
those requested in the query.  Also, make the algorithm used for both
PortStatus and PortDataCounters the same.

Reviewed-by: Arthur Kepner <arthur.kepner@intel.com>
Reviewed-by: Breyer, Scott J <scott.j.breyer@intel.com>
Signed-off-by: Ira Weiny <iweiny@gmail.com>
Signed-off-by: Jubin John <jubin.john@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>