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: Ic68a12ef7c12222b1300981282161c971b561dc1
diff --git a/command/guid.cpp b/command/guid.cpp
index 26e73e8..56b459f 100644
--- a/command/guid.cpp
+++ b/command/guid.cpp
@@ -92,15 +92,13 @@
     if (matchPtr == nullptr)
     {
         using namespace sdbusplus::bus::match::rules;
-        sdbusplus::bus::bus bus{ipmid_get_sd_bus_connection()};
+        sdbusplus::bus_t bus{ipmid_get_sd_bus_connection()};
 
         matchPtr = std::make_unique<sdbusplus::bus::match_t>(
             bus,
             path_namespace(guidObjPath) + type::signal() +
                 member("PropertiesChanged") + interface(propInterface),
-            [](sdbusplus::message::message&) {
-                cache::guid = getSystemGUID();
-            });
+            [](sdbusplus::message_t&) { cache::guid = getSystemGUID(); });
     }
 }