genirq: Return the IRQ name from free_irq()

This allows callers to get back at them instead of having to store it in
another variable.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h
index 53144e7..a6fba48 100644
--- a/include/linux/interrupt.h
+++ b/include/linux/interrupt.h
@@ -155,7 +155,7 @@
 request_percpu_irq(unsigned int irq, irq_handler_t handler,
 		   const char *devname, void __percpu *percpu_dev_id);
 
-extern void free_irq(unsigned int, void *);
+extern const void *free_irq(unsigned int, void *);
 extern void free_percpu_irq(unsigned int, void __percpu *);
 
 struct device;