DBus: use PDI constants for ObjectMapper

Use the PDI-defined constants for ObjectMapper calls instead of
duplicating them here.

Tested: Inspection only.

Change-Id: I74cb19ff7c23131bb9d69256ae85e1cf98785c99
Signed-off-by: Alexander Hansen <alexander.hansen@9elements.com>
diff --git a/dbus/dbuspassiveredundancy.cpp b/dbus/dbuspassiveredundancy.cpp
index 2ccd490..76dded9 100644
--- a/dbus/dbuspassiveredundancy.cpp
+++ b/dbus/dbuspassiveredundancy.cpp
@@ -20,6 +20,7 @@
 #include <sdbusplus/bus/match.hpp>
 #include <sdbusplus/exception.hpp>
 #include <sdbusplus/message.hpp>
+#include <xyz/openbmc_project/ObjectMapper/common.hpp>
 
 #include <array>
 #include <iostream>
@@ -29,6 +30,8 @@
 #include <variant>
 #include <vector>
 
+using ObjectMapper = sdbusplus::common::xyz::openbmc_project::ObjectMapper;
+
 namespace pid_control
 {
 
@@ -115,9 +118,8 @@
 void DbusPassiveRedundancy::populateFailures(void)
 {
     auto mapper = passiveBus.new_method_call(
-        "xyz.openbmc_project.ObjectMapper",
-        "/xyz/openbmc_project/object_mapper",
-        "xyz.openbmc_project.ObjectMapper", "GetSubTree");
+        ObjectMapper::default_service, ObjectMapper::instance_path,
+        ObjectMapper::interface, ObjectMapper::method_names::get_sub_tree);
     mapper.append("/", 0, std::array<const char*, 1>{redundancy::interface});
     std::unordered_map<
         std::string, std::unordered_map<std::string, std::vector<std::string>>>