doc: document watchdog_device parameter

Commit 8d8d4a936ab73d8449a3574f969b17a90ef9428e introduced the
configuration parameter resources.watchdog_device. This commit
introduces the resources section and watchdog_device parameter in
corosync.conf.5.

Signed-off-by: Adrian Vondendriesch <adrian.vondendriesch@credativ.de>
Reviewed-by: Jan Friesse <jfriesse@redhat.com>

man/corosync.conf.5

@@ -60,6 +60,9 @@ This top level directive contains configuration options for nodes in cluster.
 .TP
 qb { }
 This top level directive contains configuration options related to libqb.
+.TP
+resources { }
+This top level directive contains configuration options for resources.
 
 .PP
 The 
@@ -640,6 +643,17 @@ Native means one of shm or socket, depending on what is supported by OS. On syst
 with support for both, SHM is selected. SHM is generally faster, but need to allocate
 ring buffer file in /dev/shm.
 
+.PP
+Within the
+.B resources
+directive it is possible to specify options for resources.
+
+Possible option is:
+.TP
+watchdog_device
+This configuration option controls which watchdog device corosync try to bind to.
+The default value is /dev/watchdog. The value "no" disables the watchdog feature.
+
 .SH "FILES"
 .TP
 /etc/corosync/corosync.conf