qcacld-3.0: Advertise NAN support only if INI is enabled

Under get_supported_features vendor command driver is advertising
NAN capability by checking only the Firmware support. If NAN is
disabled through INI it should not advertize this support.

Add an INI parameter check before advertizing NAN capability

Change-Id: Ib48044a04500d6619b97d5ca1c3431ee64d7e096
CRs-Fixed: 2288204