Suppres debug output from optimized builds

see also dc9eb38a27

Even though it may be useful to get timing information from
optimized builds, this should not be enabled by default.

gtk2_ardour/midi_region_view.cc

@@ -1115,7 +1115,9 @@ MidiRegionView::model_changed()
 		return;
 	}
 
+#ifndef NDEBUG
 	Timing t;
+#endif
 
 	if (_active_notes) {
 		// Currently recording
@@ -1255,8 +1257,10 @@ MidiRegionView::model_changed()
 	_marked_for_velocity.clear ();
 	_pending_note_selection.clear ();
 
+#ifndef NDEBUG
 	t.update ();
 	std::cerr << "REDISPLAY(model) of " << region()->name() << " complete after " << t.elapsed_msecs() << std::endl;
+#endif
 }
 
 void
@@ -1266,7 +1270,9 @@ MidiRegionView::view_changed()
 		return;
 	}
 
+#ifndef NDEBUG
 	Timing t;
+#endif
 
 	if (_active_notes) {
 		// Currently recording
@@ -1329,8 +1335,10 @@ MidiRegionView::view_changed()
 	update_sysexes();
 	update_patch_changes ();
 
+#ifndef NDEBUG
 	t.update ();
 	std::cerr << "REDISPLAY(view) of " << region()->name() << " complete after " << t.elapsed_msecs() << std::endl;
+#endif
 }
 
 void