timer stats: Fix del_timer_sync() and try_to_del_timer_sync()

These functions forgot to run timer_stats_timer_clear_start_info().  It's
unobvious what effect this has and whether it matters much - we won't be
printing it out anyway if the timer's detached.

Untested, just an Ingo trollpatch.

[ Nevertheless correct - tglx ]

Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: johnstul@us.ibm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>