The zephyr-app-commands directive can output a helpful hint to the user
when they are trying to build a sample that is in the Zephyr tree,
telling them to ensure they are in the root folder of the Zephyr repo.
Update all doc pages that were using :app: instead of :zephyr-app: so
that the hint is displayed.
Signed-off-by: Benjamin Cabé <benjamin@zephyrproject.org>
Improved the wording of the Hardening tool documentation to better
reflect that it does suggestions for both options that could be enabled
for improved security, as well as options that should be disabled for
they may expose to vulnerabilities. Also fixed the "Usage" section which
was stale.
Signed-off-by: Benjamin Cabé <benjamin@zephyrproject.org>