Qt4: remove useless IPv6 option

We have been able to autodetect this for ages

modules/gui/qt4/components/open_panels.cpp

@@ -418,7 +418,6 @@ NetOpenPanel::NetOpenPanel( QWidget *_parent, intf_thread_t *_p_intf ) :
     CONNECT( ui.portSpin, valueChanged( int ), this, updateMRL() );
     CONNECT( ui.addressText, textChanged( QString ), this, updateMRL());
     CONNECT( ui.timeShift, clicked(), this, updateMRL());
-    CONNECT( ui.ipv6, clicked(), this, updateMRL());
 
     ui.protocolCombo->addItem( "" );
     ui.protocolCombo->addItem("HTTP", QVariant("http"));
@@ -446,7 +445,6 @@ void NetOpenPanel::updateProtocol( int idx_proto ) {
 
     ui.timeShift->setEnabled( idx_proto == UDP_PROTO ||
                               idx_proto == UDPM_PROTO );
-    ui.ipv6->setEnabled( idx_proto == UDP_PROTO );
     ui.addressText->setEnabled( idx_proto != UDP_PROTO );
     ui.portSpin->setEnabled( idx_proto == UDP_PROTO ||
                              idx_proto == UDPM_PROTO );
@@ -505,10 +503,6 @@ void NetOpenPanel::updateMRL() {
             break;
         case UDP_PROTO:
             mrl = "udp://@";
-            if( ui.ipv6->isEnabled() && ui.ipv6->isChecked() )
-            {
-                mrl += "[::]";
-            }
             mrl += QString(":%1").arg( ui.portSpin->value() );
             emit methodChanged("udp-caching");
             break;

modules/gui/qt4/ui/open_net.ui

@@ -111,13 +111,6 @@
         </property>
        </widget>
       </item>
-      <item>
-       <widget class="QCheckBox" name="ipv6" >
-        <property name="text" >
-         <string>_("Force IPv6")</string>
-        </property>
-       </widget>
-      </item>
      </layout>
     </widget>
    </item>
@@ -144,7 +137,6 @@
   <tabstop>addressText</tabstop>
   <tabstop>portSpin</tabstop>
   <tabstop>timeShift</tabstop>
-  <tabstop>ipv6</tabstop>
  </tabstops>
  <resources/>
  <connections/>