rcu: Inline increment_cpu_stall_ticks() into its sole caller

Consolidation of the RCU flavors into one makes increment_cpu_stall_ticks()
a trivial one-line function with only one caller.  This commit therefore
inlines it.
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

kernel/rcu/tree.c

@@ -2555,7 +2555,7 @@ static void rcu_do_batch(struct rcu_data *rdp)
 void rcu_check_callbacks(int user)
 {
 	trace_rcu_utilization(TPS("Start scheduler-tick"));
-	increment_cpu_stall_ticks();
+	raw_cpu_inc(rcu_data.ticks_this_gp);
 	rcu_flavor_check_callbacks(user);
 	if (rcu_pending())
 		invoke_rcu_core();

kernel/rcu/tree.h

@@ -466,7 +466,6 @@ static void print_cpu_stall_info_begin(void);
 static void print_cpu_stall_info(int cpu);
 static void print_cpu_stall_info_end(void);
 static void zero_cpu_stall_ticks(struct rcu_data *rdp);
-static void increment_cpu_stall_ticks(void);
 static bool rcu_nocb_cpu_needs_barrier(int cpu);
 static struct swait_queue_head *rcu_nocb_gp_get(struct rcu_node *rnp);
 static void rcu_nocb_gp_cleanup(struct swait_queue_head *sq);

kernel/rcu/tree_plugin.h

@@ -1815,12 +1815,6 @@ static void zero_cpu_stall_ticks(struct rcu_data *rdp)
 	rdp->softirq_snap = kstat_softirqs_cpu(RCU_SOFTIRQ, smp_processor_id());
 }
 
-/* Increment ->ticks_this_gp for all flavors of RCU. */
-static void increment_cpu_stall_ticks(void)
-{
-	raw_cpu_inc(rcu_data.ticks_this_gp);
-}
-
 #ifdef CONFIG_RCU_NOCB_CPU
 
 /*