https://bugs.gentoo.org/808665
https://github.com/jowi24/libnetpp/pull/1

From: Sam James <sam@gentoo.org>
Date: Fri, 20 Aug 2021 02:03:34 +0100
Subject: [PATCH] Add missing <map> include

Needed for std::map. Fixes GCC 11 build.
--- a/libnet++/HttpClient.h
+++ b/libnet++/HttpClient.h
@@ -22,6 +22,7 @@
 #ifndef HTTPCLIENT_H
 #define HTTPCLIENT_H
 
+#include <map>
 #include <string>
 
 #include "TcpClient.h"