drm/amdgpu: gds bo must not be per-vm-bo

In per-vm-bo case, there could be no bo list.
But gds bo created from user space  must be passed to bo list.
So adding a check to prevent to creat gds bo as per-vm-bo.

Signed-off-by: Chunming Zhou <david1.zhou@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>