Add support for building with meson

Follow the OpenBMC herd and support a modern, comprehensible build framework.

To build with meson:
   meson build
   ninja -C build

The OpenBMC CI scripts look for meson.build before looking for CMakelists so
approval of this patch would change the build system during CI to meson.

Signed-off-by: Tom Joseph <tomjoseph@in.ibm.com>
Change-Id: I23d023d8db8048579926231841f497366ab3d516
diff --git a/src/main.cpp b/src/main.cpp
index c0564e5..e57c767 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -118,7 +118,7 @@
 static inline void

     handleListUnitsResponse(sdbusplus::asio::object_server& server,

                             std::shared_ptr<sdbusplus::asio::connection>& conn,

-                            boost::system::error_code ec,

+                            boost::system::error_code /*ec*/,

                             const std::vector<ListUnitsType>& listUnits)

 {

     // Loop through all units, and mark all units, which has to be

@@ -316,7 +316,7 @@
         "type='signal',"

         "member='StartupFinished',path='/org/freedesktop/systemd1',"

         "interface='org.freedesktop.systemd1.Manager'",

-        [&server, &conn](sdbusplus::message::message& msg) {

+        [&server, &conn](sdbusplus::message::message& /*msg*/) {

             if (!unitQueryStarted)

             {

                 unitQueryStarted = true;

diff --git a/src/srvcfg_manager.cpp b/src/srvcfg_manager.cpp
index 1818bd7..0a6fcd9 100644
--- a/src/srvcfg_manager.cpp
+++ b/src/srvcfg_manager.cpp
@@ -184,14 +184,12 @@
     {

         std::string socketUnitName(instantiatedUnitName + ".socket");

         /// Check override socket directory exist, if not create it.

-        std::experimental::filesystem::path ovrUnitFileDir(

-            systemdOverrideUnitBasePath);

+        std::filesystem::path ovrUnitFileDir(systemdOverrideUnitBasePath);

         ovrUnitFileDir += socketUnitName;

         ovrUnitFileDir += ".d";

-        if (!std::experimental::filesystem::exists(ovrUnitFileDir))

+        if (!std::filesystem::exists(ovrUnitFileDir))

         {

-            if (!std::experimental::filesystem::create_directories(

-                    ovrUnitFileDir))

+            if (!std::filesystem::create_directories(ovrUnitFileDir))

             {

                 phosphor::logging::log<phosphor::logging::level::ERR>(

                     "Unable to create the directory.",

@@ -210,8 +208,8 @@
     const std::string& objPath_, const std::string& baseUnitName_,

     const std::string& instanceName_, const std::string& serviceObjPath_,

     const std::string& socketObjPath_) :

-    server(srv_),

-    conn(conn_), objPath(objPath_), baseUnitName(baseUnitName_),

+    conn(conn_),

+    server(srv_), objPath(objPath_), baseUnitName(baseUnitName_),

     instanceName(instanceName_), serviceObjectPath(serviceObjPath_),

     socketObjectPath(socketObjPath_)

 {