Add AFNOSUPPORT error to bind

[schmee]

Happens if you do this:

    var socket = try std.os.socket(
        std.c.AF.LOCAL,
        std.c.SOCK.STREAM,
        0
    );

    const sockaddr = std.os.sockaddr.in{
        .port = std.mem.bigToNative(u16, 7777),
        .addr = @as(u32, 0),
    };
    try std.os.bind(socket, @ptrCast(*const std.os.sockaddr, &sockaddr), @sizeOf(@TypeOf(sockaddr)));

[Vexu]

Should this return error.AddressFamilyNotSupported instead? Every other case of .AFNOSUPPORT seems to do so.

[schmee]

@Vexu yes, fixed!