irq: for_each_irq_desc() move to irqnr.h

Impact: cleanup

before CONFIG_SPARSE_IRQ age, for_each_irq_desc() sat in irqnr.h and
could be called from generic code.

CONFIG_SPARSE_IRQ breaks this assumption, but SPARSE_IRQ version
for_each_irq_desc() also can move into irqnr.h easily.

Also, this patch unifies CONFIG_SPARSE_IRQ and !CONFIG_SPARSE_IRQ
for_each_irq_desc().

Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/include/linux/irq.h b/include/linux/irq.h
index 98564dc..69da275 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -202,33 +202,17 @@
 
 #ifndef CONFIG_SPARSE_IRQ
 extern struct irq_desc irq_desc[NR_IRQS];
-
-static inline struct irq_desc *irq_to_desc(unsigned int irq)
-{
-	return (irq < NR_IRQS) ? irq_desc + irq : NULL;
-}
-static inline struct irq_desc *irq_to_desc_alloc_cpu(unsigned int irq, int cpu)
-{
-	return irq_to_desc(irq);
-}
-
-#else
-
-extern struct irq_desc *irq_to_desc(unsigned int irq);
-extern struct irq_desc *irq_to_desc_alloc_cpu(unsigned int irq, int cpu);
+#else /* CONFIG_SPARSE_IRQ */
 extern struct irq_desc *move_irq_desc(struct irq_desc *old_desc, int cpu);
 
-# define for_each_irq_desc(irq, desc)		\
-	for (irq = 0, desc = irq_to_desc(irq); irq < nr_irqs; irq++, desc = irq_to_desc(irq))
-# define for_each_irq_desc_reverse(irq, desc)                          \
-	for (irq = nr_irqs - 1, desc = irq_to_desc(irq); irq >= 0; irq--, desc = irq_to_desc(irq))
-
 #define kstat_irqs_this_cpu(DESC) \
 	((DESC)->kstat_irqs[smp_processor_id()])
 #define kstat_incr_irqs_this_cpu(irqno, DESC) \
 	((DESC)->kstat_irqs[smp_processor_id()]++)
 
-#endif
+#endif /* CONFIG_SPARSE_IRQ */
+
+extern struct irq_desc *irq_to_desc_alloc_cpu(unsigned int irq, int cpu);
 
 static inline struct irq_desc *
 irq_remap_to_desc(unsigned int irq, struct irq_desc *desc)