sdbusplus: use shorter type aliases

The sdbusplus headers provide shortened aliases for many types.
Switch to using them to provide better code clarity and shorter
lines.  Possible replacements are for:
  * bus_t
  * exception_t
  * manager_t
  * match_t
  * message_t
  * object_t
  * slot_t

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I46a5eec210002af84239af74a93c830b1d4a13f1
diff --git a/redfish-core/lib/account_service.hpp b/redfish-core/lib/account_service.hpp
index f8ba322..9a8142d 100644
--- a/redfish-core/lib/account_service.hpp
+++ b/redfish-core/lib/account_service.hpp
@@ -1584,7 +1584,7 @@
 
         crow::connections::systemBus->async_method_call(
             [asyncResp, username, password](const boost::system::error_code ec2,
-                                            sdbusplus::message::message& m) {
+                                            sdbusplus::message_t& m) {
             if (ec2)
             {
                 userErrorMessageHandler(m.get_error(), asyncResp, username, "");
@@ -1900,8 +1900,7 @@
     crow::connections::systemBus->async_method_call(
         [asyncResp, username, password(std::move(password)),
          roleId(std::move(roleId)), enabled, newUser{std::string(*newUserName)},
-         locked](const boost::system::error_code ec,
-                 sdbusplus::message::message& m) {
+         locked](const boost::system::error_code ec, sdbusplus::message_t& m) {
         if (ec)
         {
             userErrorMessageHandler(m.get_error(), asyncResp, newUser,