Single server binary is no longer statically linked on Linux

[ctron]

The single server binary was statically linked for 0.8. But since then it is actually dynamically linked.

We should revert to a statically linked binary, however it seems link this isn't as easy as expected. All kind of attempts to switch to static failed. The result always is a dynamically linked binary.

One assumption is, that the use of pkg-config in most of the libraries takes precedence over "vendored". And so it ends up using the -l flags from pkg-config, but doesn't add a "statically linked" flag.