Add mass_seccomp_editor.py for seccomp editing

This tool lets you work with large swaths of seccomp files quickly,
determining which have missing syscalls, and allowing fast editing
for all of them.

BUG=None
TEST=cd mass_seccomp_editor; python3 -m unittest
TEST=Ran many times for glibc noexec patch

Change-Id: I7dbad6eff431d41e23d31465a444b209520e953a
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/third_party/toolchain-utils/+/3101468
Tested-by: Jordan R Abrahams <ajordanr@google.com>
Auto-Submit: Jordan R Abrahams <ajordanr@google.com>
Commit-Queue: George Burgess <gbiv@chromium.org>
Reviewed-by: George Burgess <gbiv@chromium.org>
2 files changed