Fix typos in tests/

Reviewed-by: Ryan Moeller <ryan@ixsystems.com>
Reviewed-by: Richard Laager <rlaager@wiktel.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Closes #9246

tests/zfs-tests/tests/functional/inuse/inuse_001_pos.ksh

@@ -80,7 +80,7 @@ dumpdev=`dumpadm | grep "Dump device" | awk '{print $3}'`
 [[ -z "$dumpdev" ]] && log_untested "No dump device has been configured"
 
 [[ "$dumpdev" != "$diskslice" ]] && \
-    log_untested "Dump device has not been been configured to $diskslice"
+    log_untested "Dump device has not been configured to $diskslice"
 
 log_note "Attempt to zpool the dump device"
 unset NOINUSE_CHECK

tests/zfs-tests/tests/functional/inuse/inuse_004_pos.ksh

@@ -48,8 +48,8 @@ verify_runnable "global"
 function cleanup
 {
 	#
-	# Essentailly this is the default_cleanup routine but I cannot get it
-	# to work correctly.  So its reproduced below.  Still need to full
+	# Essentially this is the default_cleanup routine but I cannot get it
+	# to work correctly.  So its reproduced below.  Still need to fully
 	# understand why default_cleanup does not work correctly from here.
 	#
         log_must zfs umount $TESTPOOL/$TESTFS

tests/zfs-tests/tests/functional/inuse/inuse_008_pos.ksh

@@ -69,7 +69,7 @@ function verify_assertion #slices
 		echo "y" | newfs -v $t > /dev/null 2>&1
 		(( $? !=0 )) && \
 			log_fail "newfs over exported pool " \
-				"failes unexpected."
+				"fails unexpectedly."
 	done
 
 	return 0