Codec2: remove some unused code

MyReflector code is copied into MyComponentInstance.

C2TypedFieldSupportedValues was meant as a helper class that should not be
part of C2Param.h. It will be reworked to reuse C2FieldSupportedValues to
avoid having to copy to-from the Codec2 struct.

Bug: 64121714
Test: build
Change-Id: Ibb6fb87f69470b721fe7bd1871c4f2400411b6b9