WPS 2.0: Validate WPS attributes in management frames and WSC messages

WPS 2.0: Validate WPS attributes in management frames and WSC messages

If CONFIG_WPS_STRICT is set, validate WPS IE(s) in management frames and
reject the frames if any of the mandatory attributes is missing or if an
included attribute uses an invalid value. In addition, verify that all
mandatory attributes are included and have valid values in the WSC
messages.