pkg-ubuntu: add build pipeline Ubuntu 22.04, 24.04

This commit add necessary files for building debian .deb package and
shell script to build for Ubuntu 22.04 and 24.04. You can use it by
running `extras/packaging/build_packages.sh` script.

Change-Id: I91ba97cbe932ff4207072dcb2f9d2b2887de236a
diff --git a/extras/packaging/gnu-linux/debian/control b/extras/packaging/gnu-linux/debian/control
new file mode 100644
index 0000000..e069138
--- /dev/null
+++ b/extras/packaging/gnu-linux/debian/control
@@ -0,0 +1,17 @@
+Source: dhtnet
+Section: net
+Priority: optional
+Maintainer: Louis Maillard <louis.maillard@savoirfairelinux.com>
+Build-Depends: cmake, debhelper-compat (= 12)
+Standards-Version: 4.5.0
+Homepage: https://git.jami.net/savoirfairelinux/dhtnet
+Vcs-Git: https://git.jami.net/savoirfairelinux/dhtnet.git
+
+Package: dhtnet
+Architecture: any
+Multi-Arch: foreign
+Depends: ${misc:Depends}, ${shlibs:Depends}
+Conflicts: dsh
+Description: DHTNet, a Lightweight Peer-to-Peer Communication Library,
+ allows you to connect with a device simply by knowing its public key and
+ efficiently manages peer discovery and connectivity establishment, including NAT traversal.