Bluetooth: controller: Fix build error for non Nordic plaforms

Direction finding is implemented only for Nordic link layer.
Build was failing due to missing header files for Openisa (RiskV).
Added dummy lll_df_types.h header file to OpenISA lower link layer.

Signed-off-by: Piotr Pryga <piotr.pryga@nordicsemi.no>
1 file changed