Qt: deactivate noise video filter

It has become so slow in 1.2.0, especially on Win32, that this isn't
funny.
Maybe the new rands() are slower (4d6247fd)
Ref #4290

modules/gui/qt4/components/extended_panels.cpp

@@ -159,7 +159,7 @@ ExtVideo::ExtVideo( intf_thread_t *_p_intf, QTabWidget *_parent ) :
 
     SETUP_VFILTER( motiondetect )
 
-    SETUP_VFILTER( noise )
+//    SETUP_VFILTER( noise )
 
     SETUP_VFILTER( psychedelic )