Revert "drm/amdgpu: add debugfs amdgpu_reset_level"

This reverts commit 5bd8d53f.

This commit breaks the reset logic for aldebaran, revert it for now.
Will move the mask inside the reset handler.

Fixes: 5bd8d53f

 ("drm/amdgpu: add debugfs amdgpu_reset_level")
Signed-off-by: Victor Zhao <Victor.Zhao@amd.com>
Reviewed-by: Lijo Lazar <lijo.lazar@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>