Update banker_spyeye_mutex.py

The mutex as seen at https://malwr.com/analysis/ZmMzNTk0YWU5OGM4NDUzNjg2YmEzYjcxNTFjNTBkM2I/ is "C:\zXeRY3a_PtW|00000000" and didn’t matched the original signature because of additional "C:\" at the start.