genirq: Remove unneeded forward declaration

The protoype of irq_flow_handler_t is independent of irq_data, so remove
unneeded forward declaration.

Signed-off-by: Dawei Li <[email protected]>
Signed-off-by: Thomas Gleixner <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

Author: Dawei Li

include/linux/irqhandler.h

@@ -8,7 +8,7 @@
  */
 
 struct irq_desc;
-struct irq_data;
+
 typedef	void (*irq_flow_handler_t)(struct irq_desc *desc);
 
 #endif