According to the standards of data rate units (see https://en.wikipedia.org/wiki/Data_rate_units), an MB is 1,000,000 whereas an MiB is 1,048,576.

When calculating bandwidth in lnet_selftest, we are dividing by 1,048,576 to get the MiB/s but reporting it as MB/s.

This ticket is to fix the reported units to be MiB/s for accuracy.