MINOR: httpclient: add the server to the proxy

Add the raw and ssl server to the proxy list so they can be freed during
the deinit() of HAProxy. As a side effect the 2 servers need to have a
different ID so the SSL one was renamed "<HTTPSCLIENT>".
diff --git a/src/http_client.c b/src/http_client.c
index 7c0ac08..fad3368 100644
--- a/src/http_client.c
+++ b/src/http_client.c
@@ -703,7 +703,7 @@
 	httpclient_srv_ssl->uweight = 0;
 	httpclient_srv_ssl->xprt = xprt_get(XPRT_SSL);
 	httpclient_srv_ssl->use_ssl = 1;
-	httpclient_srv_ssl->id = strdup("<HTTPCLIENT>");
+	httpclient_srv_ssl->id = strdup("<HTTPSCLIENT>");
 	if (!httpclient_srv_ssl->id)
 		goto err;
 
@@ -713,6 +713,11 @@
 	httpclient_proxy->next = proxies_list;
 	proxies_list = httpclient_proxy;
 
+	/* link the 2 servers in the proxy */
+	httpclient_srv_raw->next = httpclient_proxy->srv;
+	httpclient_srv_ssl->next = httpclient_srv_raw;
+	httpclient_proxy->srv = httpclient_srv_ssl;
+
 	return 0;
 
 err: