[PATCH] uml: make hw_controller_type->release exist only for archs needing it

With Chris Wedgwood <cw@f00f.org>

As suggested by Chris, we can make the "just added" method ->release
conditional to UML only (better: to archs requesting it, i.e.  only UML
currently), so that other archs don't get this unneeded crud, and if UML
won't need it any more we can kill this.

Signed-off-by: Paolo 'Blaisorblade' Giarrusso <blaisorblade@yahoo.it>
CC: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/include/linux/irq.h b/include/linux/irq.h
index b68ad80..7fc1022 100644
--- a/include/linux/irq.h
+++ b/include/linux/irq.h
@@ -47,7 +47,10 @@
 	void (*ack)(unsigned int irq);
 	void (*end)(unsigned int irq);
 	void (*set_affinity)(unsigned int irq, cpumask_t dest);
+	/* Currently used only by UML, might disappear one day.*/
+#ifdef CONFIG_IRQ_RELEASE_METHOD
 	void (*release)(unsigned int irq, void *dev_id);
+#endif
 };
 
 typedef struct hw_interrupt_type  hw_irq_controller;