[ARM] S3C: Make IRQ_EINT sleep control common

Move the IRQ_EINT sleep control to be available to all
s3c impelmentations. Since s3c_irqext_wake is not large,
place it in arch/arm/plat-s3c/pm.c as adding it to a new
file would be a waste of compile time.

Signed-off-by: Ben Dooks <ben-linux@fluff.org>
diff --git a/arch/arm/mach-s3c24a0/include/mach/irqs.h b/arch/arm/mach-s3c24a0/include/mach/irqs.h
index ae8c0e3..83ce2a7 100644
--- a/arch/arm/mach-s3c24a0/include/mach/irqs.h
+++ b/arch/arm/mach-s3c24a0/include/mach/irqs.h
@@ -70,6 +70,8 @@
 #define IRQ_EINT17	S3C2410_IRQ(49)
 #define IRQ_EINT18	S3C2410_IRQ(50)
 
+#define IRQ_EINT_BIT(x) ((x) - IRQ_EINT00)
+
 /* SUB IRQS */
 #define IRQ_S3CUART_RX0		S3C2410_IRQ(51)	/* 67 */
 #define IRQ_S3CUART_TX0		S3C2410_IRQ(52)