rangetimer: fix x86 build failure for the !HRTIMERS case

the timer peek function was on the wrong side of an ifdef,
breaking for the !HRTIMERs case. Just provide an empty inline
for that case since it doesn't make sense in that scenario.
Signed-off-by: NArjan van de Ven <arjan@linux.intel.com>

include/linux/hrtimer.h

@@ -283,6 +283,8 @@ static inline int hrtimer_is_hres_active(struct hrtimer *timer)
 	return timer->base->cpu_base->hres_active;
 }
 
+extern void hrtimer_peek_ahead_timers(void);
+
 /*
  * The resolution of the clocks. The resolution value is returned in
  * the clock_getres() system call to give application programmers an
@@ -305,6 +307,7 @@ static inline int hrtimer_is_hres_active(struct hrtimer *timer)
  * is expired in the next softirq when the clock was advanced.
  */
 static inline void clock_was_set(void) { }
+static inline void hrtimer_peek_ahead_timers(void) { }
 
 static inline void hres_timers_resume(void) { }
 
@@ -328,7 +331,6 @@ extern ktime_t ktime_get_real(void);
 
 
 DECLARE_PER_CPU(struct tick_device, tick_cpu_device);
-extern void hrtimer_peek_ahead_timers(void);
 
 
 /* Exported timer functions: */