rcu: delete __cpuinit usage from all rcu files

The __cpuinit type of throwaway sections might have made sense
some time ago when RAM was more constrained, but now the savings
do not offset the cost and complications.  For example, the fix in
commit 5e427ec2d0 ("x86: Fix bit corruption at CPU resume time")
is a good example of the nasty type of bugs that can be created
with improper use of the various __init prefixes.

After a discussion on LKML[1] it was decided that cpuinit should go
the way of devinit and be phased out.  Once all the users are gone,
we can then finally remove the macros themselves from linux/init.h.

This removes all the drivers/rcu uses of the __cpuinit macros
from all C files.

[1] https://lkml.org/lkml/2013/5/20/589

Cc: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Cc: Josh Triplett <josh@freedesktop.org>
Cc: Dipankar Sarma <dipankar@in.ibm.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/kernel/rcutree.h b/kernel/rcutree.h
index 4a39d36..b383258 100644
--- a/kernel/rcutree.h
+++ b/kernel/rcutree.h
@@ -521,10 +521,10 @@
 static bool rcu_is_callbacks_kthread(void);
 #ifdef CONFIG_RCU_BOOST
 static void rcu_preempt_do_callbacks(void);
-static int __cpuinit rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
+static int rcu_spawn_one_boost_kthread(struct rcu_state *rsp,
 						 struct rcu_node *rnp);
 #endif /* #ifdef CONFIG_RCU_BOOST */
-static void __cpuinit rcu_prepare_kthreads(int cpu);
+static void rcu_prepare_kthreads(int cpu);
 static void rcu_cleanup_after_idle(int cpu);
 static void rcu_prepare_for_idle(int cpu);
 static void rcu_idle_count_callbacks_posted(void);