Log Message:
security/cfs: Update to 1.5.0b

Shift to a continution fork of cfs, which has many of our patches
applied, and which is buildable with modern rpcgen.

Tested on NetBSD 9 amd64 with an encrypted directory that was made
with older cfs.

Upstream changes are mainly modernization of the code and removal of
accomodations for the 80s and 90s.