Add NODE and HOST parameters in "server create" help text

Add optional parameters "NODE" and "HOST" in the help text of the
server create comand for --availability-zone.

Co-Authored-By: tianhui <tianhui@awcloud.com>
Change-Id: I4faea8a3d3aecb21ec535e55c238c71745fc68cb
Task: 24274
Story: 2003313

Author: 2 people

openstackclient/compute/v2/server.py

@@ -711,7 +711,12 @@ def get_parser(self, prog_name):
         parser.add_argument(
             '--availability-zone',
             metavar='<zone-name>',
-            help=_('Select an availability zone for the server'),
+            help=_('Select an availability zone for the server. '
+                   'Host and node are optional parameters. '
+                   'Availability zone in the format '
+                   '<zone-name>:<host-name>:<node-name>, '
+                   '<zone-name>::<node-name>, <zone-name>:<host-name> '
+                   'or <zone-name>'),
         )
         parser.add_argument(
             '--host',