Add deps to files used by backwards compatibility checker

Any used files need to be in the dependencies list for rules. In this
case, this is more than what's actually read in the script, but the
older ones shouldn't change as much, and replicating the logic is
non-trivial.

Bug: 130111713
Test: run with RBE, no longer see error about file not found
Change-Id: I88baf541ce6250a5dbf7b8a7d6b8005ed7cf5cc6