radv: Only enable sparse features on Polaris and newer.
On Fiji, the CTS image can cause a hang when these are enabled. Let's enable them for Polaris and newer only, for now.
The Fiji hang will be tracked in issue #4136
On Fiji, the CTS image can cause a hang when these are enabled. Let's enable them for Polaris and newer only, for now.
The Fiji hang will be tracked in issue #4136