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: I17807e986cefa6a3d9e757c533ac373035438aed
diff --git a/src/main.cpp b/src/main.cpp
index e81150a..2c94340 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -91,7 +91,7 @@
     std::shared_ptr<sdbusplus::asio::connection> conn =
         std::make_shared<sdbusplus::asio::connection>(io);
     conn->request_name("xyz.openbmc_project.bios_bmc_smm_error_logger");
-    sdbusplus::bus::bus& bus = static_cast<sdbusplus::bus::bus&>(*conn);
+    sdbusplus::bus_t& bus = static_cast<sdbusplus::bus_t&>(*conn);
 
     std::unique_ptr<rde::FileHandlerInterface> fileIface =
         std::make_unique<rde::ExternalStorerFileWriter>();