Revert "CHROMIUM: seccomp_filters: move to btrees"

Revert "CHROMIUM: seccomp_filters: move to btrees"

This reverts commit 92dd4371dbd71b313c2318f93649923bb3742884.

https://lists.ubuntu.com/archives/kernel-team/2012-January/018695.html

"At this point, since there are no consumers of the old API, and it
will be almost certainly replaced by the BPF API, I think in the face
of the 5-year support of the LTS release, we should probably just
remove all of the seccomp_filter patches from Ubuntu." - Kees Cook

Signed-off-by: Leann Ogasawara <leann.ogasawara@canonical.com>