user32/tests: Fix test failures on 64-bit testbot VMs.

dlls/user32/tests/clipboard.c

@@ -1737,7 +1737,10 @@ static void test_handles( HWND hwnd )
     h = SetClipboardData( 0xdeadbeef, hfixed );
     ok( h == hfixed, "got %p\n", h );
     ok( is_fixed( h ), "expected fixed mem %p\n", h );
+#ifndef _WIN64
+    /* testing if hfixed2 is freed triggers an exception on Win64 */
     ok( is_freed( hfixed2 ) || broken( !is_freed( hfixed2 )) /* < Vista */, "expected freed mem %p\n", hfixed2 );
+#endif
 
     r = CloseClipboard();
     ok( r, "gle %d\n", GetLastError() );