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: If9a7314dade153dd7dbd149a76352aca8257839d
diff --git a/item_updater.cpp b/item_updater.cpp
index b57650a..3173481 100644
--- a/item_updater.cpp
+++ b/item_updater.cpp
@@ -21,7 +21,7 @@
 using namespace sdbusplus::xyz::openbmc_project::Common::Error;
 using namespace phosphor::logging;
 
-void ItemUpdater::createActivation(sdbusplus::message::message& m)
+void ItemUpdater::createActivation(sdbusplus::message_t& m)
 {
     using SVersion = server::Version;
     using VersionPurpose = SVersion::VersionPurpose;
@@ -233,7 +233,7 @@
             elog<InternalFailure>();
         }
     }
-    catch (const sdbusplus::exception::exception& e)
+    catch (const sdbusplus::exception_t& e)
     {
         log<level::ERR>("Error in Mapper call");
         elog<InternalFailure>();
@@ -253,7 +253,7 @@
         auto strParam = std::get<std::string>(currentChassisState);
         return (strParam != CHASSIS_STATE_OFF);
     }
-    catch (const sdbusplus::exception::exception& e)
+    catch (const sdbusplus::exception_t& e)
     {
         log<level::ERR>("Error in fetching current Chassis State",
                         entry("MAPPERRESPONSE=%s",