[S390] irq: merge irq.c and s390_ext.c

Merge irq.c and s390_ext.c into irq.c. That way all external interrupt
related functions are together.

Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/arch/s390/include/asm/irq.h b/arch/s390/include/asm/irq.h
index 1544b90..ba7b01c 100644
--- a/arch/s390/include/asm/irq.h
+++ b/arch/s390/include/asm/irq.h
@@ -2,6 +2,7 @@
 #define _ASM_IRQ_H
 
 #include <linux/hardirq.h>
+#include <linux/types.h>
 
 enum interruption_class {
 	EXTERNAL_INTERRUPT,
@@ -31,4 +32,11 @@
 	NR_IRQS,
 };
 
+typedef void (*ext_int_handler_t)(unsigned int, unsigned int, unsigned long);
+
+int register_external_interrupt(u16 code, ext_int_handler_t handler);
+int unregister_external_interrupt(u16 code, ext_int_handler_t handler);
+void service_subclass_irq_register(void);
+void service_subclass_irq_unregister(void);
+
 #endif /* _ASM_IRQ_H */