gnt-{instance,backup}(8) --nic is actually --net

Fix a typo in the man pages that used the wrong option name.

Signed-off-by: Guido Trotter <ultrotter@google.com>
Reviewed-by: Iustin Pop <iustin@google.com>

man/gnt-backup.sgml

@@ -168,7 +168,7 @@
 
       <para>
         The NICs of the instances can be specified via the
-        <option>--nic</option> option. By default, one NIC is created
+        <option>--net</option> option. By default, one NIC is created
         for the instance, with the MAC set to the original MAC of the
         instance (as it was at export time). Each NIC can take up to
         three parameters (all optional):

man/gnt-instance.sgml

@@ -148,7 +148,7 @@
 
         <para>
           The NICs of the instances can be specified via the
-          <option>--nic</option> option. By default, one NIC is
+          <option>--net</option> option. By default, one NIC is
           created for the instance, with a random MAC, and connected
           to the default bridge. Each NIC can take up to three
           parameters (all optional):
@@ -1200,12 +1200,12 @@ instance5: 11225
         </para>
 
         <para>
-          The <option>--nic
+          The <option>--net
           add:<replaceable>options</replaceable></option> option will
           add a new NIC to the instance. The available options are the
           same as in the <command>add</command> command (mac, ip,
-          bridge). The <option>--nice remove</option> will remove the
-          last NIC of the instance, while the <option>--nic
+          bridge). The <option>--net remove</option> will remove the
+          last NIC of the instance, while the <option>--net
           <replaceable>N</replaceable>:<replaceable>options</replaceable></option>
           option will change the parameters of the Nth instance NIC.
         </para>