Update Csocket to a newer version with compile fixes for OpenSSL with
disabled compression support. Since we don't get zlib as an transitive
dependency anymore, also add zlib as an explicit dependency.

Signed-off-by: Jonas Gorski <jonas.gorski@gmail.com>

Signed-off-by: Stefan Weil <sw@weilnetz.de>

Signed-off-by: Jonas Gorski <jogo@openwrt.org>

Fixes compilation with musl.

Requires GCC 4.7 or newer, so broken for octeon.

Signed-off-by: Jonas Gorski <jogo@openwrt.org>

ZNC uses a map to cache channel memebers on join. Unfortunately uclibc++
uses a naive linked-list implementation with horrible performance, which
can cause joins to take a few minutes on popular channels.

Therefore Switch to libstdc++ which uses a much more performant hashmap.
ZNC by itself is already rather large, so the added footprint of
libstd++ vs uclibc++ does not matter that much anyway.

Should fix #11778.

Signed-off-by: Jonas Gorski <jogo@openwrt.org>

Signed-off-by: Jonas Gorski <jogo@openwrt.org>

Signed-off-by: Jonas Gorski <jogo@openwrt.org>