fixed usage of wrong C roles (e.g. `:c:struct:` instead of `:c:type:`)
which Breathe tolerates but can cause trouble when using other systems.
Signed-off-by: Benjamin Cabé <benjamin@zephyrproject.org>
Move this section under the kernel and alongside other core and low
level features that are tied to the kernel.
Signed-off-by: Anas Nashif <anas.nashif@intel.com>
