libpldmresponder: create PDR when the D-Bus object path exists

On a system where this D-Bus object path does not exist, it should
not create a PDR when the D-Bus object specified here is not found.

Tested: In the PDR config files, the PDR is successfully created when
the objectPath of the D-Bus exists, otherwise, skipped the current
config and the PDR is not created.

Signed-off-by: George Liu <liuxiwei@inspur.com>
Change-Id: Ib59fa79cc28d5712161bfb971c37c86c363bafb0
diff --git a/common/utils.hpp b/common/utils.hpp
index e84ed7b..8c5c4f5 100644
--- a/common/utils.hpp
+++ b/common/utils.hpp
@@ -144,6 +144,9 @@
   public:
     virtual ~DBusHandlerInterface() = default;
 
+    virtual std::string getService(const char* path,
+                                   const char* interface) const = 0;
+
     virtual void setDbusProperty(const DBusMapping& dBusMap,
                                  const PropertyValue& value) const = 0;
 
@@ -181,7 +184,8 @@
      *
      *  @throw sdbusplus::exception::SdBusError when it fails
      */
-    std::string getService(const char* path, const char* interface) const;
+    std::string getService(const char* path,
+                           const char* interface) const override;
 
     /** @brief Get property(type: variant) from the requested dbus
      *