In 1.6, Zephyr switched to "unified kernel" and new API set. Older kernel API is supported, but marked as deprecated and leads to warnings.
This provides time and sleep together with the usual ticks_us/_ms/_diff and sleep_us/ms family. We also provide access to Zephyr's high precision timer as ticks_cpu(). Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>