Add support for ARMv8 AArch64 (the 64 bit ARM instruction set).


git-svn-id: svn://svn.valgrind.org/valgrind/trunk@13770 a5019735-40e9-0310-863c-91ae7b9d1cf9
diff --git a/coregrind/pub_core_threadstate.h b/coregrind/pub_core_threadstate.h
index 7a9611b..694dddc 100644
--- a/coregrind/pub_core_threadstate.h
+++ b/coregrind/pub_core_threadstate.h
@@ -88,6 +88,8 @@
    typedef VexGuestPPC64State VexGuestArchState;
 #elif defined(VGA_arm)
    typedef VexGuestARMState   VexGuestArchState;
+#elif defined(VGA_arm64)
+   typedef VexGuestARM64State VexGuestArchState;
 #elif defined(VGA_s390x)
    typedef VexGuestS390XState VexGuestArchState;
 #elif defined(VGA_mips32)