Create ipsets with family inet6 in an ipv6-only cluster

[uablrek]

What this PR does / why we need it:

This PR maked ipsets to be created with family inet6 in an ipv6-only cluster.

Without this PR ipsets are created for ipv4 and attempts to insert ipv6 addresses fails. Most traffic is lost, but not all. Failing syncs also floods the logs.

Which issue(s) this PR fixes

Fixes #67799

Special notes for your reviewer:

There was a isIPv6 flag in the ipsetInfo structure. That field is no longer used and is removed.

It looks like a reason for the flag is that ipsets that is not of hash type does not have the family attribute. However that is checked here. See also #68338

Release note:

Corrected family type (inet6) for ipsets in ipv6-only clusters

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[uablrek]

Sorry about the delayed CLA. The corporation CLA shall be ready Monday I have been assured.

[uablrek]

CLA should be signed now

[uablrek]

Another CLA attempt...

[m1093782566]

/ok-to-test

/cc @islinwb

for review.

[islinwb]

Thanks @uablrek
/lgtm

[nikhita]

/kind bug

/assign @m1093782566
for approval

[nikhita]

/retest

[uablrek]

Any news on when this can be merged?

[uablrek]

Can you please merge this PR in the 1.13 release? @nikhita @m1093782566

[m1093782566]

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: m1093782566, uablrek

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[m1093782566]

/milestone v1.13