[PATCH] x86_64: e820.c needs pgtable.h

arch/x86_64/kernel/e820.c:42: error: 'MAXMEM' undeclared here (not in a function)

Cc: Andi Kleen <ak@muc.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/x86_64/kernel/e820.c b/arch/x86_64/kernel/e820.c
index b8eee4c..e56c2ad 100644
--- a/arch/x86_64/kernel/e820.c
+++ b/arch/x86_64/kernel/e820.c
@@ -17,6 +17,7 @@
 #include <linux/kexec.h>
 #include <linux/module.h>
 
+#include <asm/pgtable.h>
 #include <asm/page.h>
 #include <asm/e820.h>
 #include <asm/proto.h>