Prefer 'on' | 'off' over 'yes' | 'no' for bool options

Update some docs and test cases to use 'on' | 'off' as the preferred
value for bool options.

Reviewed-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
diff --git a/qemu-options.hx b/qemu-options.hx
index 9172d51..d0410f0 100644
--- a/qemu-options.hx
+++ b/qemu-options.hx
@@ -5027,7 +5027,7 @@
         Note the use of quotes due to the x509 distinguished name
         containing whitespace, and escaping of ','.
 
-    ``-object authz-listfile,id=id,filename=path,refresh=yes|no``
+    ``-object authz-listfile,id=id,filename=path,refresh=on|off``
         Create an authorization object that will control access to
         network services.
 
@@ -5072,7 +5072,7 @@
 
              # |qemu_system| \\
                  ... \\
-                 -object authz-simple,id=auth0,filename=/etc/qemu/vnc-sasl.acl,refresh=yes \\
+                 -object authz-simple,id=auth0,filename=/etc/qemu/vnc-sasl.acl,refresh=on \\
                  ...
 
     ``-object authz-pam,id=id,service=string``