Add missing parameter

I think the code was broken before and guess this is the correct fix
@JeroenDeDauw it looks, like you are using PHPStorm. Its a great IDE, but the code stubs for some PHP modules are sometimes not correct or just too old:) Maybe the `$criteria` parameter was obligatory in earlier version of MongoDB php driver? Or it can be just an error in the stub.
I looked in the PHPStorm issue tracker and it seems to be the case: http://youtrack.jetbrains.com/issues/WI?q=mongo+State%3A+Open+