hrtimer: Cleanup direct access to wall_to_monotonic

Provides an accessor function to replace hrtimer.c's
direct access of wall_to_monotonic.

This will allow wall_to_monotonic to be made static as
planned in Documentation/feature-removal-schedule.txt

Signed-off-by: John Stultz <johnstul@us.ibm.com>
LKML-Reference: <1279068988-21864-9-git-send-email-johnstul@us.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
diff --git a/include/linux/time.h b/include/linux/time.h
index 9072df8..a57e0f6 100644
--- a/include/linux/time.h
+++ b/include/linux/time.h
@@ -126,7 +126,8 @@
 
 unsigned long get_seconds(void);
 struct timespec current_kernel_time(void);
-struct timespec __current_kernel_time(void); /* does not hold xtime_lock */
+struct timespec __current_kernel_time(void); /* does not take xtime_lock */
+struct timespec __get_wall_to_monotonic(void); /* does not take xtime_lock */
 struct timespec get_monotonic_coarse(void);
 
 #define CURRENT_TIME		(current_kernel_time())