BUG/MINOR: cli: don't call the kw->io_release if kw->parse failed

The io_release() callback of the cli_kw is supposed to be used to clean
what an io_handler() has made. It is called once the work in the IO
handler is finished, or when the connection was aborted by the client.

This patch fixes a bug where the io_release callback was called even
when the parse() callback failed. Which means that the io_release() could
called even if the io_handler() was not called.

Should be backported in every versions that have a cli_kw->release().
(as far as 1.7)

(cherry picked from commit 90b098c921e15f912dbde42658e34780f0ba446d)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
diff --git a/src/cli.c b/src/cli.c
index 9a9f80f..c063fbf 100644
--- a/src/cli.c
+++ b/src/cli.c
@@ -570,10 +570,19 @@
 
 	appctx->io_handler = kw->io_handler;
 	appctx->io_release = kw->io_release;
-	/* kw->parse could set its own io_handler or ip_release handler */
-	if ((!kw->parse || kw->parse(args, payload, appctx, kw->private) == 0) && appctx->io_handler) {
-		appctx->st0 = CLI_ST_CALLBACK;
-	}
+
+	if (kw->parse && kw->parse(args, payload, appctx, kw->private) != 0)
+		goto fail;
+
+	/* kw->parse could set its own io_handler or io_release handler */
+	if (!appctx->io_handler)
+		goto fail;
+
+	appctx->st0 = CLI_ST_CALLBACK;
+	return 1;
+fail:
+	appctx->io_handler = NULL;
+	appctx->io_release = NULL;
 	return 1;
 }