treewide: be explicit about dependence on oid-array.h

Signed-off-by: Elijah Newren <newren@gmail.com>
Acked-by: Calvin Wan <calvinwan@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

commit-graph.c

@@ -12,6 +12,7 @@
 #include "hash-lookup.h"
 #include "commit-graph.h"
 #include "object-store.h"
+#include "oid-array.h"
 #include "alloc.h"
 #include "hashmap.h"
 #include "replace-object.h"