Fix order of soinfo links (repairs libcxx tests).

Change-Id: Iee9de09657351cd6a7512784ca797e4b84cdd98b
diff --git a/linker/linker.cpp b/linker/linker.cpp
index 610489e..ac470a5 100644
--- a/linker/linker.cpp
+++ b/linker/linker.cpp
@@ -1778,8 +1778,8 @@
 
 void soinfo::add_child(soinfo* child) {
   if (has_min_version(0)) {
-    this->children.push_front(child);
-    child->parents.push_front(this);
+    child->parents.push_back(this);
+    this->children.push_back(child);
   }
 }