Migrate IUsbGadget implementation to AIDL

This change migrates IUsbGadget implementation to AIDL.
Port of commit <d6d0b7d2ca5066988ee90889dccd00c06d64b694>.

Bug: 218791946
Test: USB function switch success and AIDL service is running.
Change-Id: I9613178d3cd2f9abd5396e4af763a257a8ef62a7
8 files changed