Fix bitmask arithmetic to match up with decoding.

These changes make it so that sensor
values can be properly decoded in
CarDiagnosticEvent and make their way
to CarDiagnosticManager untampered.

Test: ./diagnostic_injector.py diagjson.example
Change-Id: Id44d618b06b5945c98c8d1db118bb8689dc1e629
2 files changed