drm/amd/display: Fix hubp check in set_cursor_position

Found by smatch:
drivers/gpu/drm/amd/amdgpu/../display/dc/core/dc_stream.c:298
dc_stream_set_cursor_position() error: we previously assumed 'hubp'
could be null (see line 294)
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
Reviewed-by: Tony Cheng <Tony.Cheng@amd.com>
Acked-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

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

@@ -263,7 +263,6 @@ bool dc_stream_set_cursor_position(
 		struct input_pixel_processor *ipp = pipe_ctx->plane_res.ipp;
 		struct mem_input *mi = pipe_ctx->plane_res.mi;
 		struct hubp *hubp = pipe_ctx->plane_res.hubp;
-		struct transform *xfm = pipe_ctx->plane_res.xfm;
 		struct dpp *dpp = pipe_ctx->plane_res.dpp;
 		struct dc_cursor_position pos_cpy = *position;
 		struct dc_cursor_mi_param param = {
@@ -294,11 +293,11 @@ bool dc_stream_set_cursor_position(
 		if (mi != NULL && mi->funcs->set_cursor_position != NULL)
 			mi->funcs->set_cursor_position(mi, &pos_cpy, &param);
 
-		if (hubp != NULL && hubp->funcs->set_cursor_position != NULL)
-			hubp->funcs->set_cursor_position(hubp, &pos_cpy, &param);
+		if (!hubp)
+			continue;
 
-		if (xfm != NULL && xfm->funcs->set_cursor_position != NULL)
-			xfm->funcs->set_cursor_position(xfm, &pos_cpy, &param, hubp->curs_attr.width);
+		if (hubp->funcs->set_cursor_position != NULL)
+			hubp->funcs->set_cursor_position(hubp, &pos_cpy, &param);
 
 		if (dpp != NULL && dpp->funcs->set_cursor_position != NULL)
 			dpp->funcs->set_cursor_position(dpp, &pos_cpy, &param, hubp->curs_attr.width);

drivers/gpu/drm/amd/display/dc/inc/hw/transform.h

@@ -259,13 +259,6 @@ struct transform_funcs {
 			struct transform *xfm_base,
 			const struct dc_cursor_attributes *attr);
 
-	void (*set_cursor_position)(
-			struct transform *xfm_base,
-			const struct dc_cursor_position *pos,
-			const struct dc_cursor_mi_param *param,
-			uint32_t width
-			);
-
 };
 
 const uint16_t *get_filter_2tap_16p(void);