libcab: add camera algorithm bridge

This initial version creates a service, arc-camera-algo, that adapts
the camera algorithm library. A camera HAL can utilize the camera
algorithm bridge to access the camera algorithm through IPC that is
built between the bridge and adapter.
The arc-camera-algo service, together with the camera algorithm, is
sandboxed using minijail0 with chroot and seccomp-bpf filter applied
such that minimum kernel surface is exposed and access to /dev/video* is
denied.

BUG=b/38298347
TEST='emerge-kevin arc-camera3-libcab-test'
     'cros deploy ssh://kevin arc-camera3-libcab-test'
     'sudo -u arc-camera -g arc-camera /usr/bin/libcab_test'
CQ-DEPEND=CL:509376

Change-Id: I3e5684cb78563923f659a9b0a257756f1a7278f8
Reviewed-on: https://chromium-review.googlesource.com/510412
Commit-Ready: Hung-yu Wu <hywu@chromium.org>
Tested-by: Hung-yu Wu <hywu@chromium.org>
Reviewed-by: Ricky Liang <jcliang@chromium.org>
21 files changed