r21950: After discussion with the Apple and Linux client maintainers,

r21950: After discussion with the Apple and Linux client maintainers,
changing the FindFirst response for the UNIX_INFO2 level to include
a length field before the name. The name is not required to be null
terminated. The length field does not count any null.

Also add call to chflags(2) in the default VFS module so that this
will work be default on BSD-derived platform. Add UNIX-INFO2 test
to the build farm to get some non-BSD coverage.

Jeremy and Jerry, please review for inclusion in 3.0.25.