locktorture: Increase Hamming distance between call_rcu_chain and rcu_call_chains

One letter difference is really not enough, so this commit changes
call_rcu_chain to call_rcu_chain_list.

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Neeraj Upadhyay (AMD) <neeraj.iitr10@gmail.com>