sched: Spelling fix

Signed-off-by: Andrei Epure <epure.andrei@gmail.com>
Cc: trivial@kernel.org
Cc: peterz@infradead.org
Link: http://lkml.kernel.org/r/1362996200-2674-1-git-send-email-epure.andrei@gmail.comSigned-off-by: Ingo Molnar <mingo@kernel.org>

kernel/sched/fair.c

@@ -652,7 +652,7 @@ static u64 sched_slice(struct cfs_rq *cfs_rq, struct sched_entity *se)
 }
 
 /*
- * We calculate the vruntime slice of a to be inserted task
+ * We calculate the vruntime slice of a to-be-inserted task.
  *
  * vs = s/w
  */