rcu: Return false instead of 0 in rcu_nocb_adopt_orphan_cbs()

Return false instead of 0 in rcu_nocb_adopt_orphan_cbs() as this has
bool as return type.

Signed-off-by: Pranith Kumar <bobby.prani@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Tested-by: Paul Gortmaker <paul.gortmaker@windriver.com>

kernel/rcu/tree_plugin.h

@@ -2581,7 +2581,7 @@ static bool __maybe_unused rcu_nocb_adopt_orphan_cbs(struct rcu_state *rsp,
 						     struct rcu_data *rdp,
 						     unsigned long flags)
 {
-	return 0;
+	return false;
 }
 
 static void __init rcu_boot_init_nocb_percpu_data(struct rcu_data *rdp)