patch 9.0.0318: clearing screen causes flicker

Problem:    Clearing screen causes flicker.
Solution:   Do not clear but redraw in more cases.  Add () to "wait_return".

src/option.c

@@ -2184,7 +2184,7 @@ skip:
 	    // make sure all characters are printable
 	    trans_characters(IObuff, IOSIZE);
 
-	    ++no_wait_return;		// wait_return done later
+	    ++no_wait_return;		// wait_return() done later
 	    emsg((char *)IObuff);	// show error highlighted
 	    --no_wait_return;