devel/boost-jam build messages

[Kenta Suzumoto]

Hi. I needed to install boost-jam for another port and I'm seeing a lot of things like this in the (very long) compile:

[...]
compile.c++.with-pch bin.v2/libs/math/build/clang-linux-3.3/release/threading-multi/riemann_zetal.o
compile.c++.with-pch bin.v2/libs/math/build/clang-linux-3.3/release/threading-multi/sph_legendrel.o
compile.c++.with-pch bin.v2/libs/math/build/clang-linux-3.3/release/threading-multi/sph_neumannl.o
[...]

linux? Does the source need patching to reflect that we're building on FreeBSD? Do the upstream developers
need to change this? It's just kind of annoying seeing a bunch of "linux" stuff in the build log. I hope they know
that this software is being used on other open source OSes too. Maybe it's just a cosmetic problem.