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: I0eb22958103519924e336a2260a4d48015848c3e
diff --git a/vpd-manager/server.cpp b/vpd-manager/server.cpp
index 8fd8476..14d2151 100644
--- a/vpd-manager/server.cpp
+++ b/vpd-manager/server.cpp
@@ -21,7 +21,7 @@
 namespace server
 {
 
-Manager::Manager(bus::bus& bus, const char* path) :
+Manager::Manager(bus_t& bus, const char* path) :
     _com_ibm_VPD_Manager_interface(bus, path, interface, _vtable, this),
     _intf(bus.getInterface())
 {