tools/unitctl: adjust readme for socket addresses

CONTROL_SOCKET_ADDRESS is singular, adds note that the flag can be
specified multiple times, and adjusts code to print
CONTROL_SOCKET_ADDRESS as singular.

Signed-off-by: Gabor Javorszky <g.javorszky@f5.com>
Signed-off-by: Andrew Clayton <a.clayton@nginx.com>

Author: javorszky

tools/unitctl/README.md

@@ -69,7 +69,7 @@ Commands:
 
 Options:
   -s, --control-socket-address <CONTROL_SOCKET_ADDRESS>
-          Path (unix:/var/run/unit/control.sock), tcp address with port (127.0.0.1:80), or URL
+          Path (unix:/var/run/unit/control.sock), tcp address with port (127.0.0.1:80), or URL. This flag can be specified multiple times.
   -w, --wait-timeout-seconds <WAIT_TIME_SECONDS>
           Number of seconds to wait for control socket to become available
   -t, --wait-max-tries <WAIT_MAX_TRIES>

tools/unitctl/unitctl/src/unitctl.rs

@@ -14,7 +14,8 @@ pub(crate) struct UnitCtl {
         short = 's',
         long = "control-socket-address",
         value_parser = parse_control_socket_address,
-        help = "Path (unix:/var/run/unit/control.sock), tcp address with port (127.0.0.1:80), or URL"
+        value_name = "CONTROL_SOCKET_ADDRESS",
+        help = "Path (unix:/var/run/unit/control.sock), tcp address with port (127.0.0.1:80), or URL. This flag can be specified multiple times."
     )]
     pub(crate) control_socket_addresses: Option<Vec<ControlSocket>>,