sched/ext: Fix scx vs sched_delayed

Commit 98442f0c ("sched: Fix delayed_dequeue vs
switched_from_fair()") forgot about scx :/

Fixes: 98442f0c ("sched: Fix delayed_dequeue vs switched_from_fair()")
Reported-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lkml.kernel.org/r/20241030104934.GK14555@noisy.programming.kicks-ass.net