docs: device-mapper: fixed spelling mistakes in documentation

found/fixed the following typos

- flushs -> flushes

in `Documentation/admin-guide/device-mapper/delay.rst`

Signed-off-by: Soham Metha <[e-mail]>
Signed-off-by: Mikulas Patocka <[e-mail]>

Documentation/admin-guide/device-mapper/delay.rst

···
 ========
 
 Device-Mapper's "delay" target delays reads and/or writes
-and/or flushs and optionally maps them to different devices.
+and/or flushes and optionally maps them to different devices.
 
 Arguments::
 
···
 	#!/bin/sh
 	#
 	# Create mapped device delaying write and flush operations for 400ms and
-	# splitting reads to device $1 but writes and flushs to different device $2
+	# splitting reads to device $1 but writes and flushes to different device $2
 	# to different offsets of 2048 and 4096 sectors respectively.
 	#
 	dmsetup create delayed --table "0 `blockdev --getsz $1` delay $1 2048 0 $2 4096 400"
···
 ::
 	#!/bin/sh
 	#
-	# Create mapped device delaying reads for 50ms, writes for 100ms and flushs for 333ms
+	# Create mapped device delaying reads for 50ms, writes for 100ms and flushes for 333ms
 	# onto the same backing device at offset 0 sectors.
 	#
 	dmsetup create delayed --table "0 `blockdev --getsz $1` delay $1 0 50 $2 0 100 $1 0 333"