RoutingCoordinatorService's {add,remove,update}Route methods
all end up calling netd's *RouteParcel methods.
Make callers explicitly generate and pass in the parcel to the
manager class instead of having them pass in a RouteInfo and
having the service class convert the RouteInfo to a parcel.
Also remove the {add,remove,update}Route methods from
RoutingCoordinatorManager since they are unused.
This is a no-op refactor that simplifies upcoming changes.
RoutingCoordinator is not a stable interface and is not used
across the platform/mainline boundary, so there are no version
skew considerations.
Bug: 394308861
Test: atest ConnectivityCoverageTests
Flag: EXEMPT no-op refactor
Change-Id: Iedf4c9bc28c3fc8c289db421857acddc8c694990