Remove custom version of getPtr

Now that sdbusplus variant supports std::get_if, we can remove our
custom, mapbox namespaced implementation that does the same thing.

Change-Id: I854c473003e28e41dd45dba08ca683433f1c1774
Signed-off-by: Ed Tanous <ed.tanous@intel.com>
diff --git a/redfish-core/lib/update_service.hpp b/redfish-core/lib/update_service.hpp
index f600c14..d5ecf24 100644
--- a/redfish-core/lib/update_service.hpp
+++ b/redfish-core/lib/update_service.hpp
@@ -260,8 +260,8 @@
                                 }
 
                                 const std::string *swActivationStatus =
-                                    mapbox::getPtr<const std::string>(
-                                        activation);
+                                    sdbusplus::message::variant_ns::get_if<
+                                        std::string>(&activation);
                                 if (swActivationStatus == nullptr)
                                 {
                                     messages::internalError(asyncResp->res);
@@ -401,7 +401,8 @@
                                 return;
                             }
                             const std::string *swInvPurpose =
-                                mapbox::getPtr<const std::string>(it->second);
+                                sdbusplus::message::variant_ns::get_if<
+                                    std::string>(&it->second);
                             if (swInvPurpose == nullptr)
                             {
                                 BMCWEB_LOG_DEBUG
@@ -426,7 +427,8 @@
                             BMCWEB_LOG_DEBUG << "Version found!";
 
                             const std::string *version =
-                                mapbox::getPtr<const std::string>(it->second);
+                                sdbusplus::message::variant_ns::get_if<
+                                    std::string>(&it->second);
 
                             if (version == nullptr)
                             {