many: fix remaining check-pointer-deref issues

The updated parsing_hacks.h file uncovered a bunch of extra
things that the check-pointer-deref coccinelle script flags.

This commit fixes them to make the tree check-pointer-deref clean.

src/core/execute.c

@@ -2372,6 +2372,8 @@ static int exec_shared_runtime_add(
 
         assert(m);
         assert(id);
+        assert(tmp_dir);
+        assert(var_tmp_dir);
 
         /* tmp_dir, var_tmp_dir, {net,ipc}ns_storage_socket fds are donated on success */