Add extra line about src files are part of RIC platform project

Signed-off-by: Timo Tietavainen <timo.tietavainen@nokia.com>
Change-Id: Idf0de8c3b3c8133847f14d0d0b1b38a68fcb2c67
diff --git a/src/system.cpp b/src/system.cpp
index e0852e9..ab5d102 100644
--- a/src/system.cpp
+++ b/src/system.cpp
@@ -14,6 +14,11 @@
    limitations under the License.
 */
 
+/*
+ * This source code is part of the near-RT RIC (RAN Intelligent Controller)
+ * platform project (RICP).
+*/
+
 #include "private/system.hpp"
 #include <system_error>
 #include <cerrno>