stats: Update some stats after simulated program exit behavior was changed.

The following CL delayed program exit and changed the stats for many if not
most of the SE mode regressions.

commit 2c1286865fc2542a0586ca4ff40b00765d17b348
Author: Brandon Potter <Brandon.Potter@amd.com>
Date: Wed Mar 1 14:52:23 2017 -0600

syscall-emul: Rewrite system call exit code

Change-Id: Id241f2b7d5374947597c715ee44febe1acc5ea16
Reviewed-on: https://gem5-review.googlesource.com/2656
Maintainer: Jason Lowe-Power <jason@lowepower.com>
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>

stats: update references

tests: Final reclassification of quick regressions

A few regressions were still considered long, but finished well within
the 180 seconds. They are only a handful (mostly mcf in atomic).