powerpc: Remove NO_IRQ_IGNORE

Now that legacy iSeries is gone, this is no longer used.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/machdep.h b/arch/powerpc/include/asm/machdep.h
index bf37931..42ce570 100644
--- a/arch/powerpc/include/asm/machdep.h
+++ b/arch/powerpc/include/asm/machdep.h
@@ -99,9 +99,7 @@
 
 	void		(*init_IRQ)(void);
 
-	/* Return an irq, or NO_IRQ to indicate there are none pending.
-	 * If for some reason there is no irq, but the interrupt
-	 * shouldn't be counted as spurious, return NO_IRQ_IGNORE. */
+	/* Return an irq, or NO_IRQ to indicate there are none pending. */
 	unsigned int	(*get_irq)(void);
 
 	/* PCI stuff */