s390/irq: replace setup_irq() by request_irq()

request_irq() is preferred over setup_irq(). Invocations of setup_irq()
occur after memory allocators are ready.

Per tglx[1], setup_irq() existed in olden days when allocators were not
ready by the time early interrupts were initialized.

Hence replace setup_irq() by request_irq().

[1] https://lkml.kernel.org/r/alpine.DEB.2.20.1710191609480.1971@nanos

Signed-off-by: afzal mohammed <afzal.mohd.ma@gmail.com>
Message-Id: <20200304005049.5291-1-afzal.mohd.ma@gmail.com>
[heiko.carstens@de.ibm.com: replace pr_err with panic]
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
diff --git a/drivers/s390/cio/airq.c b/drivers/s390/cio/airq.c
index 427b2e2..cb466ed 100644
--- a/drivers/s390/cio/airq.c
+++ b/drivers/s390/cio/airq.c
@@ -105,16 +105,12 @@ static irqreturn_t do_airq_interrupt(int irq, void *dummy)
 	return IRQ_HANDLED;
 }
 
-static struct irqaction airq_interrupt = {
-	.name	 = "AIO",
-	.handler = do_airq_interrupt,
-};
-
 void __init init_airq_interrupts(void)
 {
 	irq_set_chip_and_handler(THIN_INTERRUPT,
 				 &dummy_irq_chip, handle_percpu_irq);
-	setup_irq(THIN_INTERRUPT, &airq_interrupt);
+	if (request_irq(THIN_INTERRUPT, do_airq_interrupt, 0, "AIO", NULL))
+		panic("Failed to register AIO interrupt\n");
 }
 
 static inline unsigned long iv_size(unsigned long bits)