[Ranging] Register ranging service

Creating a mock RangingFrameworkInitializer to allow import

Build flag RELEASE_RANGING_STACK is guarding the service registry.
When enabled, actual RangingFrameworkInitializer is used
When disable, a mock is used which does not register ranging service

Bug: 364930449
Test: "make" with both flag enabled and disabled.
Flag: RELEASE_RANGING_STACK
Change-Id: I17474b9b6395c9ec4d73126db414f41b2ee634af