quota: Fixup comments about return value of Q_[X]GETNEXTQUOTA

We actually return ENOENT, not ESRCH, when there is no structure with
higher ID from ->get_nextdqblk. Fixup comments.
Signed-off-by: NJan Kara <jack@suse.cz>

fs/quota/quota.c

@@ -224,7 +224,7 @@ static int quota_getquota(struct super_block *sb, int type, qid_t id,
 
 /*
  * Return quota for next active quota >= this id, if any exists,
- * otherwise return -ESRCH via ->get_nextdqblk
+ * otherwise return -ENOENT via ->get_nextdqblk
  */
 static int quota_getnextquota(struct super_block *sb, int type, qid_t id,
 			  void __user *addr)
@@ -655,7 +655,7 @@ static int quota_getxquota(struct super_block *sb, int type, qid_t id,
 
 /*
  * Return quota for next active quota >= this id, if any exists,
- * otherwise return -ESRCH via ->get_nextdqblk.
+ * otherwise return -ENOENT via ->get_nextdqblk.
  */
 static int quota_getnextxquota(struct super_block *sb, int type, qid_t id,
 			    void __user *addr)