bus.hpp: fix missing-noreturn

Signed-off-by: Brad Bishop <bradleyb@fuzziesquirrel.com>
Change-Id: I734ec4f690c5a162e55ab1b69ac6b6139d942781
diff --git a/include/sdbusplus/bus.hpp b/include/sdbusplus/bus.hpp
index a2b3fb9..11e2d13 100644
--- a/include/sdbusplus/bus.hpp
+++ b/include/sdbusplus/bus.hpp
@@ -200,7 +200,7 @@
     /** @brief Process waiting dbus messages or signals forever, discarding
      * unhandled.
      */
-    void process_loop()
+    [[noreturn]] void process_loop()
     {
         while (true)
         {