Describe the samples using code-sample directive in preparation for
upcoming changes to the Zephyr documentation that will be leveraging
the provided description and metadata.
Signed-off-by: Benjamin Cabé <benjamin@zephyrproject.org>
`checkpatch.pl` requires that dts sources are indented with tabs,
fix all the spaces that slipped in while checkpatch wasn't watching.
Signed-off-by: Jordan Yates <jordan@embeint.com>
