sched: Fix UP update_avg() build warning

update_avg() is only used for SMP builds, move it to the nearest
SMP block.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <1271309399.14779.17.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

kernel/sched.c

@@ -1872,12 +1872,6 @@ static void set_load_weight(struct task_struct *p)
 	p->se.load.inv_weight = prio_to_wmult[p->static_prio - MAX_RT_PRIO];
 }
 
-static void update_avg(u64 *avg, u64 sample)
-{
-	s64 diff = sample - *avg;
-	*avg += diff >> 3;
-}
-
 static void enqueue_task(struct rq *rq, struct task_struct *p, int flags)
 {
 	update_rq_clock(rq);
@@ -2332,6 +2326,12 @@ int select_task_rq(struct rq *rq, struct task_struct *p, int sd_flags, int wake_
 
 	return cpu;
 }
+
+static void update_avg(u64 *avg, u64 sample)
+{
+	s64 diff = sample - *avg;
+	*avg += diff >> 3;
+}
 #endif
 
 /***