fix regression/typo that disabled __simple_malloc when calloc is used

commit ba819787ee introduced this
regression. since the __malloc0 weak alias was not properly provided
by __simple_malloc, use of calloc forced the full malloc to be linked.

src/malloc/lite_malloc.c

@@ -47,4 +47,4 @@ void *__simple_malloc(size_t n)
 }
 
 weak_alias(__simple_malloc, malloc);
-weak_alias(__simple_malloc, malloc0);
+weak_alias(__simple_malloc, __malloc0);