[occm] fix ovn security groups

[zetaab]

What this PR does / why we need it: the main reason for #2699 was that svcConf.allowedCIDR was not passed to ensureAndUpdateOctaviaSecurityGroup from updateloadbalancer (it was passed from ensureloadbalancer). However, I compined some of the creating values for svcConf to new function to make it little bit easier to read and remove duplicates

Which issue this PR fixes(if applicable):
fixes #2699

Special notes for reviewers:

Release note:

NONE

[zetaab]

/test openstack-cloud-controller-manager-e2e-test

[zetaab]

ping @kayrus @dulek currently ovn loadbalancers are kind of broken because of this. If using manage-security-groups="true"

[zetaab]

/kind bug

[kayrus]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: kayrus

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[zetaab]

/cherry-pick release-1.31
/cherry-pick release-1.30

[k8s-infra-cherrypick-robot]

@zetaab: #2705 failed to apply on top of branch "release-1.30":

Applying: fix ovn security groups
Using index info to reconstruct a base tree...
M	pkg/openstack/loadbalancer.go
Falling back to patching base and 3-way merge...
Auto-merging pkg/openstack/loadbalancer.go
CONFLICT (content): Merge conflict in pkg/openstack/loadbalancer.go
error: Failed to merge in the changes.
hint: Use 'git am --show-current-patch=diff' to see the failed patch
hint: When you have resolved this problem, run "git am --continue".
hint: If you prefer to skip this patch, run "git am --skip" instead.
hint: To restore the original branch and stop patching, run "git am --abort".
hint: Disable this message with "git config advice.mergeConflict false"
Patch failed at 0001 fix ovn security groups

In response to this:

/cherry-pick release-1.31
/cherry-pick release-1.30

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.

[zetaab]

/cherry-pick release-1.31

[k8s-infra-cherrypick-robot]

@zetaab: new pull request created: #2713

In response to this:

/cherry-pick release-1.31

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository.