[J-core] The meson build system is experimenting with support for FPGA toolchains

[Max Bruckner]

I was just watching a talk about the meson build system 
(https://media.ccc.de/v/ASG2017-111-meson_and_the_changing_linux_build_
landscape) and at ~11:27 Jussi Pakkanen mentioned that they are working
on support for FPGA toolchains and that they would like to see some
support that are familiar with this kind of stuff.

Of all the build systems I've tried so far, meson is the only one that
didn't make me pull my hair out, so I am really thrilled about this and
I think there might be people in the J-Core community that could help
with this effort. Maybe J-Core itself could even switch to meson at
some point, who knows.