Controllers running in HA is supported. However, if the data zone is managed by a Mobility Master, you could cluster the two controllers and it would be supported. Example Multizone setups are like the following. The Multizone setup can support up to 4 Data Zones.
1. Primary Zone: Standalone 1
Data Zone: Standalone 2
2. Primary Zone: Controller Cluster
Data Zone: Standalone
3. Primary Zone: Controller Cluster
Data Zone 1: Controller Cluster
Data Zone 2: Standalone