vtime: Always scale generic vtime accounting results

The cputime accounting in full dynticks can be a subtle
mixup of CPUs using tick based accounting and others using
generic vtime.

As long as the tick can have a share on producing these stats, we
want to scale the result against CFS precise accounting as the tick
can miss some task hiding between the periodic interrupt.

Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Li Zhong <zhong@linux.vnet.ibm.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Kevin Hilman <khilman@linaro.org>

kernel/sched/cputime.c

@@ -553,12 +553,6 @@ static void cputime_adjust(struct task_cputime *curr,
 {
 	cputime_t rtime, stime, utime, total;
 
-	if (vtime_accounting_enabled()) {
-		*ut = curr->utime;
-		*st = curr->stime;
-		return;
-	}
-
 	stime = curr->stime;
 	total = stime + curr->utime;