Fixes the API format of MagnificationConfig

1. Add a range to the parameter in setScale(), setCenterX(), setCenterY()
2. The IntDef annotation name of MagnificationMode should not be
capitalized. The constants names should also start with the same prefix
set in the IntDef annotation.
3. Adds @hide for the IntDef annotation.
4. The related constants uses consistent prefix

Bug: 208422801
Test: none
Change-Id: Ibd997c3a13385d8884e208564092d829833ae637