AIDLize createEffect params

As part of the effort to convert IAudioFlinger to AIDL, converting
some of the method arguments to pure AIDL and making their
signatures more AIDL-friendly, by avoiding multiple primitive
return value.

Test: Audio-related CTS tests from CtsMediaTestCases
Change-Id: I720ff197ae5ffd50afa8d23f8fd6f19a2246e974