block: Repeated lines in switching-sched.txt

These lines appear in this file twice - removed one occurrence.
Signed-off-by: Avishay Traeger <avishay@il.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

Documentation/block/switching-sched.txt

@@ -35,9 +35,3 @@ noop anticipatory deadline [cfq]
 # echo anticipatory > /sys/block/hda/queue/scheduler
 # cat /sys/block/hda/queue/scheduler
 noop [anticipatory] deadline cfq
-
-Each io queue has a set of io scheduler tunables associated with it. These
-tunables control how the io scheduler works. You can find these entries
-in:
-
-/sys/block/<device>/queue/iosched