A device with zephyr,deferred-init is initialized by the application, so
we cannot check if it is initialized in "the correct order". On the other
hand, a non-deferred device must not depend on a deferred-init device: this
is guaranteed to be initialized out of order.
Also adjust existing test cases and add a new test case to validate this
behavior.
Signed-off-by: Mathieu Choplain <mathieu.choplain-ext@st.com>