wpa: Reconnect ndis_events build

ndis_events build was disconnected by the MFC of
25ecdc7d52770caf1c9b44b5ec11f468f6b636f3.
Reconnect it.

This is a direct commit to stable/13.

Reported by: Scott Allendorf <scott-allendorf@uiowa.edu>
Fixes: 13f32ff71eeb7213bb9f34bdfa88c7ccecf451bc