Schneider PM8000 support

https://www.schneider-electric.com/en/download/document/PM8xxxSchneiderMIB_customer/ - MIBS

  • [ ] Please do NOT post more than 10 lines of debug information here, use a pastebin service or GitHub Gists.

(Imported from https://github.com/librenms/librenms/issues/9595, Original request by: @salt-lick)