bluetooth: controller: Guard zephyr LL specific configurations
bluetooth: controller: Guard zephyr LL specific configurations

This change prevents zephyr LL specific configurations to show up when
using an out of tree BLE controller.

BT_CTLR_ASSERT_HANDLER is used outside the controller as well,
so this is kept as is.

Signed-off-by: Rubin Gerritsen <eddef76671ab7f54bc92622aa9c9d13467ed93c1@nordicsemi.no>

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