Dell EMC VMax was rebranded to PowerMax and the related driver and
its parameters were renamed[1]. This change introduces a new resource
type to follow that rebranding.
The existing implementation to use old parameters will be deprecated
and removed in a separate change.
[1] 6995b9f9758f4b8526011954670da5602acb60cb
Partial-bug: #1951131
Change-Id: Ifde59b58915dd00ec8edf136f4bb4a48d8446025
2e56767d7a