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: Ie7375047bd567aa052d3bd35a6dd7008779a05b4
diff --git a/include/bridgingcommands.hpp b/include/bridgingcommands.hpp
index 545d24a..b771bfd 100644
--- a/include/bridgingcommands.hpp
+++ b/include/bridgingcommands.hpp
@@ -153,7 +153,7 @@
 
     IpmbRequest(const ipmbHeader* ipmbBuffer, size_t bufferLength);
 
-    void prepareRequest(sdbusplus::message::message& mesg);
+    void prepareRequest(sdbusplus::message_t& mesg);
 };
 
 struct IpmbResponse