logging: switch to lg2

After switching to C++20, it is recommended to use `phosphor::lg2`
to format log, and the correct `CODE_LINE` and `CODE_FUNC` values
can be used in log tracking.

Signed-off-by: George Liu <liuxiwei@inspur.com>
Change-Id: I4aabaafe997e13c10d655a83a9ef0071ad11126e
diff --git a/sessions_manager.cpp b/sessions_manager.cpp
index 538aaa4..5c9789b 100644
--- a/sessions_manager.cpp
+++ b/sessions_manager.cpp
@@ -3,7 +3,7 @@
 #include "main.hpp"
 #include "session.hpp"
 
-#include <phosphor-logging/log.hpp>
+#include <phosphor-logging/lg2.hpp>
 #include <sdbusplus/asio/connection.hpp>
 #include <user_channel/channel_layer.hpp>
 
@@ -12,8 +12,6 @@
 #include <iomanip>
 #include <memory>
 
-using namespace phosphor::logging;
-
 namespace session
 {
 
@@ -171,7 +169,7 @@
         return session;
     }
 
-    log<level::INFO>("No free RMCP+ sessions left");
+    lg2::info("No free RMCP+ sessions left");
 
     throw std::runtime_error("No free sessions left");
 }
@@ -265,11 +263,10 @@
         }
         if (!(session->isSessionActive(activeGrace, setupGrace)))
         {
-            log<level::INFO>(
-                "Removing idle IPMI LAN session",
-                entry("SESSION_ID=%x", session->getBMCSessionID()),
-                entry("HANDLE=%x",
-                      getSessionHandle(session->getBMCSessionID())));
+            lg2::info(
+                "Removing idle IPMI LAN session, id: {ID}, handler: {HANDLE}",
+                "ID", session->getBMCSessionID(), "HANDLE",
+                getSessionHandle(session->getBMCSessionID()));
             sessionHandleMap[getSessionHandle(session->getBMCSessionID())] = 0;
             iter = sessionsMap.erase(iter);
         }