drm/amd/display: initialize dc_transfer_func->ctx

[Why]
dc_transfer_func structs were being passed around with a null
pointer, waiting for unsuspecting programmers to dereference it.

[How]
Initialize it
Signed-off-by: David Francis <David.Francis@amd.com>
Reviewed-by: Charlene Liu <Charlene.Liu@amd.com>
Acked-by: Bhawanpreet Lakha <Bhawanpreet.Lakha@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/core/dc_stream.c

@@ -106,6 +106,7 @@ static void construct(struct dc_stream_state *stream,
 
 	stream->out_transfer_func = dc_create_transfer_func();
 	stream->out_transfer_func->type = TF_TYPE_BYPASS;
+	stream->out_transfer_func->ctx = stream->ctx;
 }
 
 static void destruct(struct dc_stream_state *stream)

drivers/gpu/drm/amd/display/dc/core/dc_surface.c

@@ -44,6 +44,7 @@ static void construct(struct dc_context *ctx, struct dc_plane_state *plane_state
 
 	plane_state->in_transfer_func = dc_create_transfer_func();
 	plane_state->in_transfer_func->type = TF_TYPE_BYPASS;
+	plane_state->in_transfer_func->ctx = ctx;
 }
 
 static void destruct(struct dc_plane_state *plane_state)