AFAIK it's certified for the application tier node only. For the database tier it's only certified on Oracle Linux 6.4 (as per the agreement with Microsoft -- See the second MOS Doc referenced below).
Oracle E-Business Suite Installation and Upgrade Notes Release 12 (12.2) for Linux x86-64 (Doc ID 1330701.1)
Certified Software on Microsoft Windows Server 2012 Hyper-V (Doc ID 1563794.1)
Received an internal response:
Oracle does not currently have plans to certify technology components such as the Database running in a Linux guest under Hyper-V at this time - only Windows guests are certified.