ping: socket: Address family not supported by protocol

The ping utility prints this curious error/warning message:

```
ping: socket: Address family not supported by protocol
```

Otherwise seems to be working just fine:

```
> ping 127.0.0.1
ping: socket: Address family not supported by protocol
PING 127.0.0.1 (127.0.0.1) 56(84) bytes of data.
64 bytes from 127.0.0.1: icmp_seq=1 ttl=64 time=0.048 ms
64 bytes from 127.0.0.1: icmp_seq=2 ttl=64 time=0.050 ms
64 bytes from 127.0.0.1: icmp_seq=3 ttl=64 time=0.043 ms
64 bytes from 127.0.0.1: icmp_seq=4 ttl=64 time=0.046 ms
```

ProblemType: Bug
DistroRelease: Ubuntu 20.10
Package: iputils-ping 3:20200821-2
ProcVersionSignature: Ubuntu 5.8.0-19.20-generic 5.8.8
Uname: Linux 5.8.0-19-generic x86_64
ApportVersion: 2.20.11-0ubuntu48
Architecture: amd64
CasperMD5CheckResult: skip
CurrentDesktop: ubuntu:GNOME
Date: Tue Sep 29 10:42:17 2020
InstallationDate: Installed on 2016-09-05 (1484 days ago)
InstallationMedia: Ubuntu-Server 16.04.1 LTS "Xenial Xerus" - Release amd64 (20160719)
SourcePackage: iputils
UpgradeStatus: No upgrade log present (probably fresh install)