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: Ibc88a5de1e7a11d332410985f29698b24aeae983
diff --git a/src/speed_select.cpp b/src/speed_select.cpp
index 2641fff..24fb11d 100644
--- a/src/speed_select.cpp
+++ b/src/speed_select.cpp
@@ -118,7 +118,7 @@
 
   public:
     using BaseOperatingConfig::BaseOperatingConfig;
-    OperatingConfig(sdbusplus::bus::bus& bus, unsigned int level_,
+    OperatingConfig(sdbusplus::bus_t& bus, unsigned int level_,
                     std::string path_) :
         BaseOperatingConfig(bus, path_.c_str(), action::defer_emit),
         path(std::move(path_)), level(level_)
@@ -130,7 +130,7 @@
   private:
     /** Objects describing all available SST configs - not modifiable. */
     std::vector<std::unique_ptr<OperatingConfig>> availConfigs;
-    sdbusplus::bus::bus& bus;
+    sdbusplus::bus_t& bus;
     const uint8_t peciAddress;
     const std::string path; ///< D-Bus path of CPU object
     const CPUModel cpuModel;
@@ -161,7 +161,7 @@
     }
 
   public:
-    CPUConfig(sdbusplus::bus::bus& bus_, uint8_t index, CPUModel model) :
+    CPUConfig(sdbusplus::bus_t& bus_, uint8_t index, CPUModel model) :
         BaseCurrentOperatingConfig(bus_, generatePath(index).c_str(),
                                    action::defer_emit),
         bus(bus_), peciAddress(index + MIN_CLIENT_ADDR),