Bluetooth: Controller: Fix k_sem_give call from Zero Latency IRQs

Fix k_sem_give() from being called from Zero Latency IRQs
when the Controller is configured with BT_CTLR_ZLI=y.

Kernel features shall not be used from Zero Latency IRQs as
these IRQs cannot be locked by the kernel to maintain
context safety of the kernel objects.

Relates to commit 92e017fd ("Bluetooth: controller:
split: Support Zero Latency IRQs") and
commit c842eef3 ("Bluetooth: controller: Add semaphore
to indicate free AD data buffers").

Signed-off-by: Vinayak Kariappa Chettimada <vich@nordicsemi.no>