6781 zpool man page needs updated to remove duplicate entry of "cannot be" where it discusses cache devices
Reviewed by: Toomas Soome <tsoome@me.com>
Reviewed by: Robert Mustacchi <rm@joyent.com>

@@ -21,11 +21,11 @@
 .\"
 .\" Copyright (c) 2007, Sun Microsystems, Inc. All Rights Reserved.
 .\" Copyright (c) 2013 by Delphix. All rights reserved.
 .\" Copyright 2016 Nexenta Systems, Inc.
 .\"
-.Dd February 15, 2016
+.Dd March 25, 2016
 .Dt ZPOOL 1M
 .Os
 .Sh NAME
 .Nm zpool
 .Nd configure ZFS storage pools

@@ -233,12 +233,12 @@
 raidz vdev types are not supported for the intent log. For more information,
 see the
 .Sx Intent Log
 section.
 .It Sy cache
-A device used to cache storage pool data. A cache device cannot be cannot be
-configured as a mirror or raidz group. For more information, see the
+A device used to cache storage pool data. A cache device cannot be configured
+as a mirror or raidz group. For more information, see the
 .Sx Cache Devices
 section.
 .El
 .Pp
 Virtual devices cannot be nested, so a mirror or raidz virtual device can only