Merge pull request #570 from John-Colvin/patch-3

arrayint.d version typo

Author: WalterBright

src/rt/arrayint.d

@@ -41,7 +41,7 @@ version (unittest)
 }
 else
 {
-    version(x86_64) //guaranteed on x86_64
+    version(X86_64) //guaranteed on x86_64
     {
         enum mmx = true;
         enum sse = true;