luci-mod-network: wireless.js: add wifi-iface macaddr random support

Add ability to choose random or custom mac address for wifi-iface.
By default the driver mac address is used and this special feature needs
to be supported by the wireless driver.

Signed-off-by: Manas Sambhus <manas.sambhus+github@gmail.com>
[ drop redundant tags and improve commit description ]
Signed-off-by: Christian Marangi <ansuelsmth@gmail.com>

modules/luci-mod-network/htdocs/luci-static/resources/view/network/wireless.js

@@ -1157,10 +1157,11 @@ return view.extend({
 					if (/^radio\d+\.network/.test(o.placeholder))
 						o.placeholder = '';
 
+					var macaddr = uci.get('wireless', radioNet.getName(), 'macaddr');
 					o = ss.taboption('advanced', form.Value, 'macaddr', _('MAC address'), _('Override default MAC address - the range of usable addresses might be limited by the driver'));
-					o.optional = true;
-					o.placeholder = radioNet.getActiveBSSID();
-					o.datatype = 'macaddr';
+					o.value('', _('driver default (%s)').format(!macaddr ? radioNet.getActiveBSSID() : _('no override')));
+					o.value('random', _('randomly generated'));
+					o.datatype = "or('random',macaddr)";
 
 					o = ss.taboption('advanced', form.Flag, 'short_preamble', _('Short Preamble'));
 					o.default = o.enabled;