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

Change-Id: I32e5f22829c03325295b180504ab5e3b5745dc95
Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
diff --git a/src/button_handler.cpp b/src/button_handler.cpp
index 4a477fa..29ae1bc 100644
--- a/src/button_handler.cpp
+++ b/src/button_handler.cpp
@@ -113,7 +113,7 @@
                           this, std::placeholders::_1));
         }
     }
-    catch (const sdbusplus::exception::exception& e)
+    catch (const sdbusplus::exception_t& e)
     {
         // The button wasn't implemented
     }
@@ -136,7 +136,7 @@
         result.read(objectData);
         return objectData.begin()->first;
     }
-    catch (const sdbusplus::exception::exception& e)
+    catch (const sdbusplus::exception_t& e)
     {
         return std::string();
     }
@@ -409,20 +409,20 @@
         method.append(HSPositionVariant);
         result = bus.call(method);
     }
-    catch (const sdbusplus::exception::exception& e)
+    catch (const sdbusplus::exception_t& e)
     {
         lg2::error("Error modifying host selector position : {ERROR}", "ERROR",
                    e);
     }
 }
 
-void Handler::debugHostSelectorReleased(sdbusplus::message::message& /* msg */)
+void Handler::debugHostSelectorReleased(sdbusplus::message_t& /* msg */)
 {
     try
     {
         increaseHostSelectorPosition();
     }
-    catch (const sdbusplus::exception::exception& e)
+    catch (const sdbusplus::exception_t& e)
     {
         lg2::error(
             "Failed power process debug host selector button press : {ERROR}",