ironic-httpd config does not work on systems with ipv6 disabled

[owenthomas17]

The current Listen directive for all interfaces does not work on systems that have ipv6 disabled. Here is an example log extracted from a deployment I've tried to get working:

+ exec /usr/sbin/httpd -DFOREGROUND
[Tue Jul 23 08:29:14.110334 2024] [core:crit] [pid 1:tid 1] (97)Address family not supported by protocol: AH00078: alloc_listener: failed to get a socket for ::
AH00526: Syntax error on line 2 of /etc/httpd/conf/httpd.conf:
Listen setup failed

[metal3-io-bot]

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[owenthomas17]

I've raised a PR addressing this issue and linked above. I've tested this on an ipv6 disabled Kubernetes cluster and it works.