drm/amdgpu: expand the emit tmz interface with trusted flag

This patch expands the emit_tmz function to support trusted flag while we want
to set command buffer in trusted mode.

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