wifi: Added new event callback to fetch hardware mode

Introduce new event callback to fetch current wifi hardware
mode.
i.e on_radio_mode_change

Bug: 68349158
Test: Compiles

(cherry-picked from 4a419dbf8550ad057574c7851e7fa0d0ca8ced0e)

Change-Id: Ib31ad152d24b91d8f184f1e16a53a47488ab4df9
1 file changed