Revert "drm/amdgpu: use BACO reset on vega20 if platform support"

This reverts commit 2172b89e

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Signed-off-by: Candice Li <candice.li@amd.com>
Reviewed-by: Hawking Zhang <Hawking.Zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>