Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Implement the PacketGetVersion() routine, which is used in
the 0.4.x versions of wpa_supplicant.

Enable -D ndis support in wpa_supplicant and add the ndis_events utility.
This allows wpa_supplicant to work with WPA and WPA2 compliant NDIS
drivers.