Clean up EffectHalInterface

Remove `isLocal`, it's a legacy from the HIDL transition times.

Make `effectId` specific to EffectHalHidl, remove usages
outside of libaudiohal.

Bug: 205884982
Test: m
Change-Id: I0486d5fb48d8cfce46aca9152136e7a1a68cf215
Merged-In: I0486d5fb48d8cfce46aca9152136e7a1a68cf215