staging: lustre: check wr_id returned by ib_poll_cq
If ib_poll_cq returned +ve without initialising ib_wc::wr_id (bug
in driver), then o2iblnd will run into unpredictable situation
because ib_wc::wr_id may refer to stale tx/rx pointer in stack.
It indicates bug in HCA driver if this happened, ko2iblnd should
output console error then close current connection.