[IA64] Fix pfn_to_nid() so the kernel compiles again for !CONFIG_DISCONTIGMEM.

Signed-off-by: David Mosberger-Tang <davidm@hpl.hp.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
diff --git a/include/asm-ia64/mmzone.h b/include/asm-ia64/mmzone.h
index 83ca404..d32f51e 100644
--- a/include/asm-ia64/mmzone.h
+++ b/include/asm-ia64/mmzone.h
@@ -15,6 +15,8 @@
 #include <asm/page.h>
 #include <asm/meminit.h>
 
+#ifdef CONFIG_DISCONTIGMEM
+
 static inline int pfn_to_nid(unsigned long pfn)
 {
 #ifdef CONFIG_NUMA
@@ -29,8 +31,6 @@
 #endif
 }
 
-#ifdef CONFIG_DISCONTIGMEM
-
 #ifdef CONFIG_IA64_DIG /* DIG systems are small */
 # define MAX_PHYSNODE_ID	8
 # define NR_NODE_MEMBLKS	(MAX_NUMNODES * 8)