genirq: Remove unused remove_percpu_irq()

remove_percpu_irq() has been unused since it was added in 2011 by
commit 31d9d9b ("genirq: Add support for per-cpu dev_id interrupts")

Remove it.

Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250420164656.112641-1-linux@treblig.org

Author: Dr. David Alan Gilbert

include/linux/irq.h

@@ -597,7 +597,6 @@ enum {
 
 struct irqaction;
 extern int setup_percpu_irq(unsigned int irq, struct irqaction *new);
-extern void remove_percpu_irq(unsigned int irq, struct irqaction *act);
 
 #ifdef CONFIG_DEPRECATED_IRQ_CPU_ONOFFLINE
 extern void irq_cpu_online(void);

kernel/irq/manage.c

@@ -2377,21 +2377,6 @@ static struct irqaction *__free_percpu_irq(unsigned int irq, void __percpu *dev_
 	return action;
 }
 
-/**
- * remove_percpu_irq - free a per-cpu interrupt
- * @irq:	Interrupt line to free
- * @act:	irqaction for the interrupt
- *
- * Used to remove interrupts statically setup by the early boot process.
- */
-void remove_percpu_irq(unsigned int irq, struct irqaction *act)
-{
-	struct irq_desc *desc = irq_to_desc(irq);
-
-	if (desc && irq_settings_is_per_cpu_devid(desc))
-		__free_percpu_irq(irq, act->percpu_dev_id);
-}
-
 /**
  * free_percpu_irq - free an interrupt allocated with request_percpu_irq
  * @irq:	Interrupt line to free