timers/posix-timers: Convert internals to use nsecs

Use the new nsec based cputime accessors as part of the whole cputime
conversion from cputime_t to nsecs.

Also convert posix-cpu-timers to use nsec based internal counters to
simplify it.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Stanislaw Gruszka <sgruszka@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Wanpeng Li <wanpeng.li@hotmail.com>
Link: http://lkml.kernel.org/r/1485832191-26889-19-git-send-email-fweisbec@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
diff --git a/include/linux/posix-timers.h b/include/linux/posix-timers.h
index 62d44c1..890de52 100644
--- a/include/linux/posix-timers.h
+++ b/include/linux/posix-timers.h
@@ -8,19 +8,9 @@
 #include <linux/alarmtimer.h>
 
 
-static inline unsigned long long cputime_to_expires(cputime_t expires)
-{
-	return (__force unsigned long long)expires;
-}
-
-static inline cputime_t expires_to_cputime(unsigned long long expires)
-{
-	return (__force cputime_t)expires;
-}
-
 struct cpu_timer_list {
 	struct list_head entry;
-	unsigned long long expires, incr;
+	u64 expires, incr;
 	struct task_struct *task;
 	int firing;
 };