sched: fix guest time accounting going faster than user time accounting

cputime_add already adds, dont do it twice.

Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/fs/proc/array.c b/fs/proc/array.c
index 27b59f5..b9be6e3 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -446,7 +446,7 @@
 			maj_flt += sig->maj_flt;
 			utime = cputime_add(utime, sig->utime);
 			stime = cputime_add(stime, sig->stime);
-			gtime += cputime_add(gtime, sig->gtime);
+			gtime = cputime_add(gtime, sig->gtime);
 		}
 
 		sid = signal_session(sig);