Add a method for wiping flags per package in RescueParty

Provide a method for RollbackManager to clear flags when performing
rollback.
Mapping of packages to namespaces comes from both the runtime records
already maintained by RescueParty and a preset DeviceConfig flag of
namespace <-> package for Mainline modules(will be pushed from GMScore).

Test: atest RescuePartyTest & manually trigger the action on local build
Bug: 173120414
Change-Id: I4773a6124b07e3291cacf71dc7b702f84b69008c