Fix regression test compile issue on OS X platform, introduced in r15113. n-i-bz

git-svn-id: svn://svn.valgrind.org/valgrind/trunk@15170 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/none/tests/libvex_test.c b/none/tests/libvex_test.c
index 2e0bfb9..e297921 100644
--- a/none/tests/libvex_test.c
+++ b/none/tests/libvex_test.c
@@ -1,6 +1,10 @@
 #include <stdio.h>
 #include <stdlib.h>
+# if !defined(VGO_darwin)
 #include <endian.h>
+# else
+#include <machine/endian.h>
+# endif
 #include "../../VEX/pub/libvex.h"
 
 Bool return_false(void*cb, Addr ad)