[WIP] SOC_U: Implemented some socket functions

This allows FTPony to work.
It's using Berkeley sockets directly since that's what the soc:U service exposes to applications.

Still WIP.
They are checked below, the only accepted value for domain type is AF_INET and the only accepted value for protocol is 0, these values are not affected by the sign, so i thought it'd be better to save a cast.