Bluetooth: Controller: Use hci.h for data-control evt handling

Use Zephyr's include/bluetooth/hci.h for HCI event
handling in data-related events.
This is the second commit in a series that transitions from
the event structures in hci.c to the ones in hci.h.

Jira: ZEP-726

Change-Id: I0e9e6f709091859af47d90b26f5e7baa830a2838
Signed-off-by: Carles Cufi <carles.cufi@nordicsemi.no>