NativeError listed 17 Winsock and 17 POSIX errors and turned every other
one into EIO. A second connect while the first is pending (WSAEALREADY,
EALREADY) and an option the host rejects (WSAENOPROTOOPT, ENOPROTOOPT)
reached the guest as EIO; on Linux a nonblocking connect (EINPROGRESS),
a send with no destination (EDESTADDRREQ), ENOTSOCK, EAFNOSUPPORT,
EOPNOTSUPP and others did too.
The translation moves to SocketError.hpp and covers the socket errors of
both hosts by name, with the FreeBSD 11 numbers. WSAESHUTDOWN stays EPIPE
as before. socketpair's own table is gone, as NativeError covers it.
(cherry picked from commit a889c98e6a59d62da289f2e6a77355d2b41a1bde)
d694aac7b4