sched: disable the hrtick for now

David Miller reported that hrtick update overhead has tripled the
wakeup overhead on Sparc64.

That is too much - disable the HRTICK feature for now by default,
until a faster implementation is found.

Reported-by: David Miller <davem@davemloft.net>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/sched_features.h b/kernel/sched_features.h
index 7c9e8f4..fda0162 100644
--- a/kernel/sched_features.h
+++ b/kernel/sched_features.h
@@ -5,7 +5,7 @@
 SCHED_FEAT(AFFINE_WAKEUPS, 1)
 SCHED_FEAT(CACHE_HOT_BUDDY, 1)
 SCHED_FEAT(SYNC_WAKEUPS, 1)
-SCHED_FEAT(HRTICK, 1)
+SCHED_FEAT(HRTICK, 0)
 SCHED_FEAT(DOUBLE_TICK, 0)
 SCHED_FEAT(ASYM_GRAN, 1)
 SCHED_FEAT(LB_BIAS, 1)