rcu: Move rcu_is_nocb_cpu() from rcupdate.h to rcu.h

The rcu_is_nocb_cpu() function is used only internally to RCU.  This
commit therefore moves its declaration from include/linux/rcupdate.h
to kernel/rcu/rcu.h.
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

include/linux/rcupdate.h

@@ -867,15 +867,6 @@ static inline int rcu_needs_cpu(u64 basemono, u64 *nextevt)
 }
 #endif /* #ifdef CONFIG_TINY_RCU */
 
-#if defined(CONFIG_RCU_NOCB_CPU_ALL)
-static inline bool rcu_is_nocb_cpu(int cpu) { return true; }
-#elif defined(CONFIG_RCU_NOCB_CPU)
-bool rcu_is_nocb_cpu(int cpu);
-#else
-static inline bool rcu_is_nocb_cpu(int cpu) { return false; }
-#endif
-
-
 /* Only for use by adaptive-ticks code. */
 #ifdef CONFIG_NO_HZ_FULL_SYSIDLE
 bool rcu_sys_is_idle(void);

kernel/rcu/rcu.h

@@ -408,4 +408,12 @@ static inline void srcutorture_get_gp_data(enum rcutorture_type test_type,
 
 #endif
 
+#if defined(CONFIG_RCU_NOCB_CPU_ALL)
+static inline bool rcu_is_nocb_cpu(int cpu) { return true; }
+#elif defined(CONFIG_RCU_NOCB_CPU)
+bool rcu_is_nocb_cpu(int cpu);
+#else
+static inline bool rcu_is_nocb_cpu(int cpu) { return false; }
+#endif
+
 #endif /* __LINUX_RCU_H */