Remove _get_compute_info from filter_scheduler.py

After patch I6de33ada6dc377e20f8df07da92244f2c150b9fe and
Ie6f104368140b69a60e124ea96ef6bf7715fe34e, in filter_scheduler.py,
_get_compute_info has no use and no one is calling it, so we
can remove it directly.

Fix bug 1228475

Change-Id: Ia85068e402b6f0b2a9ed2a809d1c1dc63e0f3041
Merge "Remove _get_compute_info from filter_scheduler.py"