lib: os: cbprintf: Add compile time switch for assert usage
lib: os: cbprintf: Add compile time switch for assert usage

Assert header is including printk header and cbprintf header
may be included by printk.h when printk is redirected to logging v2.
That creates circular includes which must be prevented by
preventing using assertion and including assert header file.

Signed-off-by: Krzysztof Chruscinski <9b6dc988558c51b0405b49b55c8e66862969844b@nordicsemi.no>

finikorg/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,finikorg/zephyr,galak/zephyr,finikorg/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,galak/zephyr,finikorg/zephyr,galak/zephyr,galak/zephyr