hostapd: hostapd_set_psk_file: fix defaut value for mac

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Bringing up of station vlan fails if the optional mac entry isn't set.
The default mac "00:00:00:00:00:00", which should match all stations,
is mistakenly set to the non used variable "isolate". This results in
a wrong formatted .psk file which has to be "vlan_id mac key".

fixes: 5aa2ddd0: hostapd: add support for wifi-station and wifi-vlan sections

Signed-off-by: Johann Neuhauser <johann@it-neuhauser.de>

package/network/services/hostapd/files/hostapd.sh

@@ -283,7 +283,7 @@ hostapd_set_psk_file() {
 	local vlan_id=""
 
 	json_get_vars mac vid key
-	set_default isolate "00:00:00:00:00:00"
+	set_default mac "00:00:00:00:00:00"
 	[ -n "$vid" ] && vlan_id="vlanid=$vid "
 	echo "${vlan_id} ${mac} ${key}" >> /var/run/hostapd-${ifname}.psk
 }