Bug#421542: nss: FTBFS on non-Linux: clean target fails due to unfixed upstream build system

[Mike Hommey]

By the way, I think it would be better for the hurd, and also for the
kfreebsd port patches if they would not clutter the linux specific
makefile but would have its own file, that would be "cleaner" and more
likely to be applied upstream.

Some factorisation could be done, though, like it is done for Linux.mk,
there could be a common makefile for glibc-based ports.

Mike