objects read: also treat ADDRESS_OF as read

Previously, all objects that are passed via address are not considered
as being read. This commit adds this case to the analysis.

Author: Norbert Manthey

src/goto-programs/goto_program.cpp

@@ -372,6 +372,9 @@ void objects_read(
   else if(src.id()==ID_address_of)
   {
     // don't traverse!
+    assert(src.operands().size()==1);
+    dest.push_back(src);
+    objects_read(src.op0(), dest);
   }
   else if(src.id()==ID_dereference)
   {