IB/hfi1: Remove leftover snoop references

A few snoop related variables were missed in the snoop/capture removal
to get out of staging. Go back and clean those up too.

Reviewed-by: Dean Luick <dean.luick@intel.com>
Signed-off-by: Dennis Dalessandro <dennis.dalessandro@intel.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>