Add a method for libbinder to wrap an accessor in a delegator

Libbinder is the only place with the IAccessorDelegator class so it must
be responsible for wrapping the IAccesses with an IAccessorDelegator.

This is used when the process with the permissions to connect to the
server over binder RPC is in a seperate process from the process that
wants to serve the IAccessor binder.

Test: atest vm_accessor_test binderRpcTest
Bug: 358427181

Change-Id: I0839f7d1b466ba9bfb13031596523314718d3677