[phobos] Why OS 'posix' for Linux but 'osx' for OSX and 'freebsd' for FreeBSD in Makefile?

[Sean Kelly]

The subject says it all.  Now that we have a unified makefile, what's the point of different target directories for each platform?  If we really have to go this route, can the target directory for linux be 'linux'?  As things stand, Linux is the only OS Brad's test suite runs against because of this issue.