add3prf.py: Add detection of LICENSE-BSD file

Add the ability to detect a BSD_LIKE license based on the existance of
LICENSE-BSD file (just like LICENSE-MIT).

Bug: 321983331
Test: Added unit test and tested against the zerocopy crate
Change-Id: I694a858e33d0c2e6865e4fae77a0287d215076fe
2 files changed