Split rkp_factory_extraction_tool into a library + binary

This way, we can unit test the library in preparation for up-coming
changes that will verify the outputs. This will serve as an extra
layer of checking for factory lines, where they want to be extra
sure that a device is outputing correct information at various stages
of the pipe.

Bug: 239838563
Test: rkp_factory_extraction_lib_test
Change-Id: I018194673820d2b31c18d30057aa533cb4fe090e
6 files changed