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: I2d7ce287e0adc0be60796a80e9bb4cca908434ce
diff --git a/nvme_main.cpp b/nvme_main.cpp
index 8552593..c9e3a96 100644
--- a/nvme_main.cpp
+++ b/nvme_main.cpp
@@ -13,7 +13,7 @@
 int main(void)
 {
 
-    sdbusplus::bus::bus bus = sdbusplus::bus::new_default();
+    sdbusplus::bus_t bus = sdbusplus::bus::new_default();
 
     sd_event* event = nullptr;
     auto eventDeleter = [](sd_event* e) { e = sd_event_unref(e); };
@@ -25,7 +25,7 @@
     // attach bus to this event loop
     bus.attach_event(sdEvent.get(), SD_EVENT_PRIORITY_NORMAL);
 
-    sdbusplus::server::manager::manager objManager(bus, NVME_OBJ_PATH_ROOT);
+    sdbusplus::server::manager_t objManager(bus, NVME_OBJ_PATH_ROOT);
 
     phosphor::nvme::Nvme objMgr(bus);