tick: Move clocksource related stuff to timekeeping.h

Move clocksource related stuff to timekeeping.h and remove the
pointless include from ntp.c

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/2714218.nM5AEfAHj0@vostro.rjw.lan
Signed-off-by: Ingo Molnar <mingo@kernel.org>

kernel/time/jiffies.c

@@ -25,7 +25,7 @@
 #include <linux/module.h>
 #include <linux/init.h>
 
-#include "tick-internal.h"
+#include "timekeeping.h"
 
 /* The Jiffies based clocksource is the lowest common
  * denominator clock source which should function on