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: I1c3acea60ea58b8a0f9a76fd32b5d0d007bf1a16
diff --git a/src/associations.cpp b/src/associations.cpp
index 75457d9..79672af 100644
--- a/src/associations.cpp
+++ b/src/associations.cpp
@@ -409,7 +409,7 @@
             addSingleAssociation(server, assocPath, endpointPath, owner,
                                  ownerPath, assocMaps);
         }
-        catch (const sdbusplus::exception::exception& e)
+        catch (const sdbusplus::exception_t& e)
         {
             // In some case the interface could not be created on DBus and an
             // exception is thrown. mapper has no control of the interface/path