radv: A Plague Tale: Requiem black flashes on RDNA2
In the game A Plague Tale: Requiem, black flashes can be observed during gameplay and seem to be caused by the ambient occlusion turning completely black for exactly 1 frame.
The issue and the workaround (RADV_DEBUG=nodcc) are the same as #8371 (closed), the fix used for RDNA3 should be applied to RDNA2 as well.
Tested with the latest mesa-git on a 6900XT.