drm/amdgpu/powerplay: Apply avfs cks-off voltages on VI

commit cf4197ed5796234a53beb71228198c7d1e678947 upstream.

Instead of EVV cks-off voltages, avfs cks-off voltages can avoid
the overshoot voltages when switching sclk.

Signed-off-by: Kenneth Feng <kenneth.feng@amd.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>