Include <limits.h> for SIZE_MAX DO NOT MERGE

Bug:34697653
Test: compile

Though typically defined in stdint.h, Android defines SIZE_MAX in
limits.h.

Change-Id: I0f6fb89d9eb55406073d6b25e599bb2745253865
diff --git a/openbsd-reallocarray.c b/openbsd-reallocarray.c
index aa70686..41a3326 100644
--- a/openbsd-reallocarray.c
+++ b/openbsd-reallocarray.c
@@ -19,6 +19,7 @@
 #include <errno.h>
 #include <stdint.h>
 #include <stdlib.h>
+#include <limits.h>
 
 /*
  * This is sqrt(SIZE_MAX+1), as s1*s2 <= SIZE_MAX