Qt: fix open dvdsimple.

Close #5935
(cherry picked from commit 4b77fc558acc1d5ff3fa80e0dd807d08284fac62)
Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>

modules/gui/qt4/components/open_panels.cpp

@@ -513,7 +513,7 @@ void DiscOpenPanel::updateMRL()
         if( !ui.dvdsimple->isChecked() )
             mrl = "dvd://" LOCALHOST;
         else
-            mrl = "dvdsimple://" LOCALHOST + discPath;
+            mrl = "dvdsimple://" LOCALHOST;
     } else if ( ui.bdRadioButton->isChecked() )
         mrl = "bluray://" LOCALHOST;
     /* VCD */