Add system dbus service for MDR V2

Add BIOS version and UUID in smbios table and provide dbus
interface for redfish to get these information.

Tested:
DC cycle the system and waiting for BIOS entering setup page.
Redfish should be able to show correct UUID.

Signed-off-by: Cheng C Yang <cheng.c.yang@linux.intel.com>
Change-Id: I0d364f27488d3efa24e4a9dde97086f09e94d2a2
diff --git a/src/mdrv2.cpp b/src/mdrv2.cpp
index c392127..07dcc6b 100644
--- a/src/mdrv2.cpp
+++ b/src/mdrv2.cpp
@@ -396,6 +396,10 @@
         dimms.emplace_back(std::make_unique<phosphor::smbios::Dimm>(
             bus, path, index, smbiosDir.dir[smbiosDirIndex].dataStorage));
     }
+
+    system.reset();
+    system = std::make_unique<System>(
+        bus, systemPath, smbiosDir.dir[smbiosDirIndex].dataStorage);
 }
 
 int MDR_V2::getTotalCpuSlot()