This change migrates IUsbGadget implementation to AIDL.
Bug: 218791946
Test: USB function switch success and AIDL service is running.
Change-Id: I7cc7070d875c26bc42f99aef84d5e5a41606223f
Signed-off-by: Ricky Niu <rickyniu@google.com>
(cherry picked from aosp commit d6d0b7d2ca5066988ee90889dccd00c06d64b694)