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: Ieb6587e32446a758676f67d9c868289cc02e50bf
diff --git a/src/Thresholds.cpp b/src/Thresholds.cpp
index ae7718e..7805dff 100644
--- a/src/Thresholds.cpp
+++ b/src/Thresholds.cpp
@@ -456,14 +456,14 @@
         try
         {
             // msg.get_path() is interface->get_object_path()
-            sdbusplus::message::message msg =
+            sdbusplus::message_t msg =
                 interface->new_signal("ThresholdAsserted");
 
             msg.append(sensor->name, interface->get_interface_name(), property,
                        assert, assertValue);
             msg.signal_send();
         }
-        catch (const sdbusplus::exception::exception& e)
+        catch (const sdbusplus::exception_t& e)
         {
             std::cerr
                 << "Failed to send thresholdAsserted signal with assertValue\n";