jobrunner/hhvm: disable perf maps, turn off jit

* Move Eval.PerfPidMap = false back to HDF file / syntax
  Upstream bug: https://github.com/facebook/hhvm/issues/2761
* Set jit = false; not beneficial for short-lived CLI scripts.

Change-Id: I14371adef60572c0fe19d30a55fd15fd1cb45f99