Make asio::object_server take const ptr to connection

No reason the parameter shouldn't be a const reference, and it enables
passing an rvalue to the constructor.

Signed-off-by: Jonathan Doman <jonathan.doman@intel.com>
Change-Id: I7bd40395c6e16b0962c39ab55adaefa8e56ceb87
diff --git a/include/sdbusplus/asio/object_server.hpp b/include/sdbusplus/asio/object_server.hpp
index 1013bd5..6ca8950 100644
--- a/include/sdbusplus/asio/object_server.hpp
+++ b/include/sdbusplus/asio/object_server.hpp
@@ -810,7 +810,7 @@
 class object_server
 {
   public:
-    object_server(std::shared_ptr<sdbusplus::asio::connection>& conn,
+    object_server(const std::shared_ptr<sdbusplus::asio::connection>& conn,
                   const bool skipManager = false) :
         conn_(conn)
     {