This is necessary when changing priorities of an entity.

v2: test the sched_list instead of num_sched.
v3: set the sched_list to NULL when there is only one entry
Signed-off-by: NChristian König <christian.koenig@amd.com>
Reviewed-by: NSonny Jiang <sonny.jiang@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210305125155.2312-1-christian.koenig@amd.com