networking: document "nc" in addition to "netcat" in netconsole.txt

It always annoyed me that the netconsole documentation didn't give me the
correct command for my distro.  Update it with a command line that actually
works on my Fedora install.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Matt Mackall <mpm@selenic.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Documentation/networking/netconsole.txt

@@ -51,7 +51,8 @@ Built-in netconsole starts immediately after the TCP stack is
 initialized and attempts to bring up the supplied dev at the supplied
 address.
 
-The remote host can run either 'netcat -u -l -p <port>' or syslogd.
+The remote host can run either 'netcat -u -l -p <port>',
+'nc -l -u <port>' or syslogd.
 
 Dynamic reconfiguration:
 ========================