arc/irq: Prepare idu_cascade_isr for irq argument removal

The irq argument of most interrupt flow handlers is unused or merily
used instead of a local variable. The handlers which need the irq
argument can retrieve the irq number from the irq descriptor.

Search and update was done with coccinelle and the invaluable help of
Julia Lawall.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Julia Lawall <Julia.Lawall@lip6.fr>
Cc: Vineet Gupta <vgupta@synopsys.com>

arch/arc/kernel/mcip.c

@@ -252,9 +252,10 @@ static struct irq_chip idu_irq_chip = {
 
 static int idu_first_irq;
 
-static void idu_cascade_isr(unsigned int core_irq, struct irq_desc *desc)
+static void idu_cascade_isr(unsigned int __core_irq, struct irq_desc *desc)
 {
 	struct irq_domain *domain = irq_desc_get_handler_data(desc);
+	unsigned int core_irq = irq_desc_get_irq(desc);
 	unsigned int idu_irq;
 
 	idu_irq = core_irq - idu_first_irq;