drm/amdgpu: fix list add issue in vram reserve

The parameter order in the list_add_tail is incorrect, it causes the
reuse of ras reserved page.

Signed-off-by: Tao Zhou <tao.zhou1@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>