trunks: Rename "chromeos" -> "brillo" in include paths and namespaces

libchromeos is transitioning to libbrillo and chromeos namespaces
and include directory is changing to brillo.

BUG=None
TEST=./build_packages --board=whirlwind

Change-Id: I40a8fc172172ec76ac934e8fb1953c0ae364d050
Reviewed-on: https://chromium-review.googlesource.com/306706
Commit-Ready: Alex Vakulenko <avakulenko@google.com>
Tested-by: Alex Vakulenko <avakulenko@google.com>
Tested-by: Alex Vakulenko <avakulenko@chromium.org>
Reviewed-by: Utkarsh Sanghi <usanghi@chromium.org>
3 files changed