genirq: Convert irq_desc.lock to raw_spinlock

Convert locks which cannot be sleeping locks in preempt-rt to
raw_spinlocks.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Acked-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/sh/kernel/irq.c b/arch/sh/kernel/irq.c
index e1913f2..d2d41d0 100644
--- a/arch/sh/kernel/irq.c
+++ b/arch/sh/kernel/irq.c
@@ -76,7 +76,7 @@
 	if (!desc)
 		return 0;
 
-	spin_lock_irqsave(&desc->lock, flags);
+	raw_spin_lock_irqsave(&desc->lock, flags);
 	for_each_online_cpu(j)
 		any_count |= kstat_irqs_cpu(i, j);
 	action = desc->action;
@@ -97,7 +97,7 @@
 
 	seq_putc(p, '\n');
 out:
-	spin_unlock_irqrestore(&desc->lock, flags);
+	raw_spin_unlock_irqrestore(&desc->lock, flags);
 	return 0;
 }
 #endif