Revert "drm/amdgpu: update kernel vcn ring test"

VCN FW depncencies revert it to unlock others

This reverts commit 3ebfa943.

Signed-off-by: Saleemkhan Jamadar <saleemkhan.jamadar@amd.com>
Acked-by: Veerabadhran Gopalakrishnan <Veerabadhran.Gopalakrishnan@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>