Adds missing code-sample directive to the Hello World sample 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>
`CLOCK_CONTROL` subsystem being selected directly at family level,
remove it from individual board configurations.
Signed-off-by: Erwan Gouriou <erwan.gouriou@st.com>
Felipe Neves