Cocoa: Use optimized drawing for the window

Default is NO.

Signed-off-by: Andreas Färber <[email protected]>
Signed-off-by: malc <[email protected]>
diff --git a/cocoa.m b/cocoa.m
index bb4325c..56c789a 100644
--- a/cocoa.m
+++ b/cocoa.m
@@ -740,6 +740,7 @@
         [normalWindow setAcceptsMouseMovedEvents:YES];
         [normalWindow setTitle:[NSString stringWithFormat:@"QEMU"]];
         [normalWindow setContentView:cocoaView];
+        [normalWindow useOptimizedDrawing:YES];
         [normalWindow makeKeyAndOrderFront:self];
 		[normalWindow center];