Bluetooth: Controller: Build hci_vendor.c also for simulation

The FICR is also modelled in simulation, but changing this
conditional compile was forgotten, so it was only being
built for real HW.
A test had provided its own version of this function so it would
avoid a runtime warning due to the lack of static address. But
this needs to be removed as it conflicts with the function
provided now always by the nordic controller SW.

Signed-off-by: Alberto Escolar Piedras <alberto.escolar.piedras@nordicsemi.no>