Make these buildable on arm64-linux.


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@13821 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/memcheck/tests/unit_libcbase.c b/memcheck/tests/unit_libcbase.c
index 752a1fb..019b67a 100644
--- a/memcheck/tests/unit_libcbase.c
+++ b/memcheck/tests/unit_libcbase.c
@@ -58,6 +58,8 @@
 // On PPC/Linux VKI_PAGE_SIZE is a variable, not a macro.
 #if defined(VGP_ppc32_linux) || defined(VGP_ppc64_linux)
 unsigned long VKI_PAGE_SIZE  = 1UL << 12;
+#elif defined(VGP_arm64_linux)
+unsigned long VKI_PAGE_SIZE  = 1UL << 16;
 #endif
 
 void test_VG_IS_XYZ_ALIGNED(void)