Adding getModelState API to sound trigger with new build fix.

This version copies the V2_0 and V2_1 implementations instead of trying
to extend them.

Test: built with the forrest tool, ie. forrest --force_cherry_pick \
build th:cl:5288240:aosp_x86-eng:git_master-without-vendor

Change-Id: Iec18b6a29c8d3d495b24fc07b5f7db95a8057f30
Bug-Id: 70206501