DolphinWX: Reimplement cheat listbox updating, but without a global

Just use event handling.

Source/Core/DolphinWX/Cheats/CheatSearchTab.cpp

@@ -313,6 +313,7 @@ void CheatSearchTab::CreateARCode(wxCommandEvent&)
 		const u32 address = m_search_results[sel].address | ((m_search_type_size & ~1) << 24);
 
 		CreateCodeDialog arcode_dlg(this, address);
+		arcode_dlg.SetExtraStyle(arcode_dlg.GetExtraStyle() & ~wxWS_EX_BLOCK_EVENTS);
 		arcode_dlg.ShowModal();
 	}
 }