drm/amdgpu: Remove unused dc_stream from amdgpu_crtc

It's no longer used. In fact, there is no more dc_stream object.
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/amdgpu/amdgpu_mode.h

@@ -436,8 +436,6 @@ struct amdgpu_crtc {
 	enum amdgpu_interrupt_state vsync_timer_enabled;
 
 	int otg_inst;
-	/* After Set Mode stream will be non-NULL */
-	const struct dc_stream *stream;
 	struct drm_pending_vblank_event *event;
 };