Fix strace build.

The previous change broke LP64.

Change-Id: I30b651daa12a1eb0b316c0f63827d823c288b029
diff --git a/Android.mk b/Android.mk
index 70a5f18..d47d4af 100644
--- a/Android.mk
+++ b/Android.mk
@@ -135,7 +135,7 @@
     -DHAVE_SIG_ATOMIC_T=1 \
     -DHAVE_SIGINFO_T=1 \
     -DHAVE_SIGINFO_T_SI_SYSCALL=1 \
-    -DHAVE_STAT64=1 \
+    -UHAVE_STAT64 \
     -DHAVE_STATFS64=1 \
     -DHAVE_STDBOOL_H=1 \
     -DHAVE_STRERROR=1 \