sched: only disable/enable interrupts if schedule() is called from non-IRQ context

sched/core.c

@@ -91,7 +91,9 @@ void context_switch(struct thread *old, struct thread *new)
 
 void __schedule(enum sched_mode mode)
 {
+	if (mode != SCHED_IRQ) {
 		ml_int_disable();
+	}
 
 	struct cpu_data *this_cpu = get_this_cpu();
 	struct runqueue *rq = &this_cpu->c_rq;
@@ -142,7 +144,9 @@ void __schedule(enum sched_mode mode)
 		context_switch(prev, next);
 	}
 
+	if (mode != SCHED_IRQ) {
 		ml_int_enable();
+	}
 }
 
 void schedule(enum sched_mode mode)