sysrepo: Implement parts of ietf-system module

Implement announcing OS name and OS release through ietf-system YANG
model [1], specifically via its top-level container system-state.
The properties are obtained from /etc/os-release file.

[1] https://tools.ietf.org/html/rfc7317

Change-Id: I82d5fd54659ea365232a3a9455dd73f84b8fd0d1
diff --git a/src/system/Sysrepo.h b/src/system/Sysrepo.h
new file mode 100644
index 0000000..0aeda9a
--- /dev/null
+++ b/src/system/Sysrepo.h
@@ -0,0 +1,23 @@
+/*
+ * Copyright (C) 2021 CESNET, https://photonics.cesnet.cz/
+ *
+ * Written by Tomáš Pecka <tomas.pecka@fit.cvut.cz>
+ *
+ */
+#pragma once
+
+#include <filesystem>
+#include <sysrepo-cpp/Session.hpp>
+#include "utils/log-fwd.h"
+
+namespace velia::system {
+
+class Sysrepo {
+public:
+    explicit Sysrepo(std::shared_ptr<::sysrepo::Session> srSession, const std::filesystem::path& osRelease);
+
+private:
+    std::shared_ptr<::sysrepo::Session> m_srSession;
+    velia::Log m_log;
+};
+}