Resolve Meson issues

This commit includes fixes in the repo:

1. Moving experimental filesystem to filesystem
2. Errors that meson identified

Signed-off-by: Ratan Gupta <ratankgupta31@gmail.com>
Change-Id: I93c77c2a434275c4da3ca4549919eaa55b57f481
diff --git a/test/test_snmp_client.cpp b/test/test_snmp_client.cpp
index 1dd9eb4..698c491 100644
--- a/test/test_snmp_client.cpp
+++ b/test/test_snmp_client.cpp
@@ -22,12 +22,11 @@
   public:
     sdbusplus::bus::bus bus;
     ConfManager manager;
-    std::string confDir;
     TestSNMPClient() :
         bus(sdbusplus::bus::new_default()), manager(bus, mgrObjPath)
     {
         char tmp[] = "/tmp/snmpClient.XXXXXX";
-        std::string confDir = mkdtemp(tmp);
+        auto confDir = mkdtemp(tmp);
         manager.dbusPersistentLocation = confDir;
     }