[PATCH] powerpc: Fix g5 build with xmon

My previous patches inadvertently broke building a G5 kernel with
CONFIG_XMON enabled. This fixes it.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

arch/powerpc/platforms/powermac/pic.c

@@ -459,7 +459,7 @@ void __init pmac_pic_init(void)
 			mpic_setup_cascade(irqctrler2->intrs[0].line,
 					   pmac_u3_cascade, mpic2);
 		}
-#ifdef CONFIG_XMON
+#if defined(CONFIG_XMON) && defined(CONFIG_PPC32)
 		{
 			struct device_node* pswitch;
 			int nmi_irq;
@@ -471,7 +471,7 @@ void __init pmac_pic_init(void)
 				setup_irq(nmi_irq, &xmon_action);
 			}
 		}
-#endif	/* CONFIG_XMON */
+#endif	/* defined(CONFIG_XMON) && defined(CONFIG_PPC32) */
 		return;
 	}
 	irqctrler = NULL;