Spam BSD.coverage.dist, similar to BSD.debug.dist, unconditionally on /usr/lib/cov

/usr/lib/cov was chosen because while there isn't a standardized upstream path
that's used for storing .gcda's, /usr/lib/cov seemed like a good symmetry with
the /usr/lib/debug for debug files for gdb, et al.

Parameterize out directories that are used to spam BSD.debug.dist,
BSD.lib32.dist, BSD.libsoft.dist, and BSD.tests.dist, and spam on
/usr/lib/cov .