inventory: Remove equinix_esxi systems

[sxa]

Checklist

• [x] commit message has one of the standard prefixes
• [ ] faq.md updated if appropriate
• [ ] other documentation is changed or added (if applicable)
• [ ] playbook changes run through VPC or QPC (if you have access)
• [x] VPC/QPC not applicable for this PR
• [x] for inventory.yml changes, bastillion/nagios/jenkins updated accordingly

[karianna]

/thaw