Stop dialogs from updating twice all the time.

I've long wondered why dialogs seem to update twice when it seems
they just need to update once. It seems it was this code. But it
was only put there to deal with a problem with code in the button
controllers that was disabled in 2007! So I'm going to try removing
it. If we start seeing weird behavior with dialogs in master, then
this will be why.

src/frontends/qt/Dialog.cpp

@@ -259,10 +259,6 @@ void Dialog::checkStatus()
 	if (canApply()) {
 		bool const readonly = isBufferReadonly();
 		enableView(!readonly || canApplyToReadOnly());
-		// refreshReadOnly() is too generous in _enabling_ widgets
-		// update dialog to disable disabled widgets again
-
-		updateView();
 	} else
 		enableView(false);
 }