use PDI constants for ObjectMapper

PDI already defines the constants we need here, use those instead of
duplicating.

Tested: Inspection only.

Change-Id: I86ad46a4aac757aa7b377b1e1709088a1e457102
Signed-off-by: Alexander Hansen <alexander.hansen@9elements.com>
diff --git a/settings.cpp b/settings.cpp
index 4564fa4..cac44c6 100644
--- a/settings.cpp
+++ b/settings.cpp
@@ -5,6 +5,9 @@
 #include <phosphor-logging/lg2.hpp>
 #include <sdbusplus/message/types.hpp>
 #include <xyz/openbmc_project/Common/error.hpp>
+#include <xyz/openbmc_project/ObjectMapper/common.hpp>
+
+using ObjectMapper = sdbusplus::common::xyz::openbmc_project::ObjectMapper;
 
 namespace settings
 {
@@ -12,10 +15,6 @@
 using namespace phosphor::logging;
 using namespace sdbusplus::error::xyz::openbmc_project::common;
 
-constexpr auto mapperService = "xyz.openbmc_project.ObjectMapper";
-constexpr auto mapperPath = "/xyz/openbmc_project/object_mapper";
-constexpr auto mapperIntf = "xyz.openbmc_project.ObjectMapper";
-
 Objects::Objects(sdbusplus::bus_t& bus, const std::vector<Interface>& filter) :
     bus(bus)
 {
@@ -52,8 +51,9 @@
 Service Objects::service(const Path& path, const Interface& interface) const
 {
     using Interfaces = std::vector<Interface>;
-    auto mapperCall =
-        bus.new_method_call(mapperService, mapperPath, mapperIntf, "GetObject");
+    auto mapperCall = bus.new_method_call(
+        ObjectMapper::default_service, ObjectMapper::instance_path,
+        ObjectMapper::interface, "GetObject");
     mapperCall.append(path);
     mapperCall.append(Interfaces({interface}));