drm/amdgpu: return error if both BOs and bo_list handle is given

Return -EINVAL when both the BOs as well as a list handle is provided in
the IOCTL.

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