genirq, irq.h: Fix kernel-doc warnings

Fix kernel-doc warnings in linux/irq.h:

  Warning(include/linux/irq.h:201): No description found for parameter 'node'
  Warning(include/linux/irq.h:201): Excess struct/union/enum/typedef member 'cpu' description in 'irq_desc'
  Warning(include/linux/irq.h:434): No description found for parameter 'node'
  Warning(include/linux/irq.h:434): Excess function parameter 'cpu' description in 'alloc_desc_masks'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
LKML-Reference: <4A3467EC.50006@oracle.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

include/linux/irq.h

@@ -157,7 +157,7 @@ struct irq_2_iommu;
  * @irqs_unhandled:	stats field for spurious unhandled interrupts
  * @lock:		locking for SMP
  * @affinity:		IRQ affinity on SMP
- * @cpu:		cpu index useful for balancing
+ * @node:		node index useful for balancing
  * @pending_mask:	pending rebalanced interrupts
  * @threads_active:	number of irqaction threads currently running
  * @wait_for_threads:	wait queue for sync_irq to wait for threaded handlers
@@ -426,7 +426,7 @@ extern int set_irq_msi(unsigned int irq, struct msi_desc *entry);
 /**
  * init_alloc_desc_masks - allocate cpumasks for irq_desc
  * @desc:	pointer to irq_desc struct
- * @cpu:	cpu which will be handling the cpumasks
+ * @node:	node which will be handling the cpumasks
  * @boot:	true if need bootmem
  *
  * Allocates affinity and pending_mask cpumask if required.