locking, sched: Annotate thread_group_cputimer as raw

The thread_group_cputimer lock can be taken in atomic context and therefore
cannot be preempted on -rt - annotate it.

In mainline this change documents the low level nature of
the lock - otherwise there's no functional difference. Lockdep
and Sparse checking will work as usual.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/sched_stats.h b/kernel/sched_stats.h
index 331e01b..87f9e36 100644
--- a/kernel/sched_stats.h
+++ b/kernel/sched_stats.h
@@ -282,10 +282,10 @@
 	if (!cputimer->running)
 		return;
 
-	spin_lock(&cputimer->lock);
+	raw_spin_lock(&cputimer->lock);
 	cputimer->cputime.utime =
 		cputime_add(cputimer->cputime.utime, cputime);
-	spin_unlock(&cputimer->lock);
+	raw_spin_unlock(&cputimer->lock);
 }
 
 /**
@@ -306,10 +306,10 @@
 	if (!cputimer->running)
 		return;
 
-	spin_lock(&cputimer->lock);
+	raw_spin_lock(&cputimer->lock);
 	cputimer->cputime.stime =
 		cputime_add(cputimer->cputime.stime, cputime);
-	spin_unlock(&cputimer->lock);
+	raw_spin_unlock(&cputimer->lock);
 }
 
 /**
@@ -330,7 +330,7 @@
 	if (!cputimer->running)
 		return;
 
-	spin_lock(&cputimer->lock);
+	raw_spin_lock(&cputimer->lock);
 	cputimer->cputime.sum_exec_runtime += ns;
-	spin_unlock(&cputimer->lock);
+	raw_spin_unlock(&cputimer->lock);
 }