Outdated socat with fixes available in upstream

[Vin01]

Hi Team!

I recently ran into an issue with socat where it would not work with `TCP6-LISTEN` and just throw 'Name of service not known` if the name to be resolved starts with a digit.

For example:

 /usr/bin/socat -x TCP-LISTEN:54323,fork TCP:1.example.com:80
2020/10/13 10:02:01 socat[26483] E getaddrinfo("1.example.com", "NULL", {5,2,1,6}, {}): Name or service not known

or following in case of TCP6-LISTEN

2020/10/13 10:03:03 socat[26497] E getaddrinfo("::ffff:1.example.com", "NULL", {5,10,1,6}, {}): Name or service not known

The bug seems to be caused by this logic: https://git.launchpad.net/ubuntu/+source/socat/tree/xio-ip.c?h=ubuntu/bionic#n167

It has been fixed upstream already so I think a patch should be feasible: https://repo.or.cz/socat.git/commitdiff/42864922e7e93d436026910c85048f9359f7a87e?hp=479d9cbbdad8e66e1450305c531be64a78c0eec8

Ubuntu socat version: 1.7.3.2 (Both Focal and Bionic)
Latest upstream version: 1.7.3.4

Please review.

Thanks!