ProductId is moved into Motherboard interface

Property ProductId is moved from root into Motherboard interface.

Tested:

To get the base board Product ID

ipmitool raw 0x30 0x93
<0xXX> - XX is the Baseboard Product ID

Signed-off-by: Suryakanth Sekar <suryakanth.sekar@linux.intel.com>
Change-Id: I11d686aea3d8b0cf244efc39c8f41348fee4414f
diff --git a/src/oemcommands.cpp b/src/oemcommands.cpp
index 43ba0fa..ad2e21e 100644
--- a/src/oemcommands.cpp
+++ b/src/oemcommands.cpp
@@ -2665,7 +2665,8 @@
             "/xyz/openbmc_project/inventory/system/board/", "Baseboard");
         const Value& propValue = getDbusProperty(
             *dbus, object.second, object.first,
-            "xyz.openbmc_project.Inventory.Item.Board", "ProductId");
+            "xyz.openbmc_project.Inventory.Item.Board.Motherboard",
+            "ProductId");
         prodId = static_cast<uint8_t>(std::get<uint64_t>(propValue));
     }
     catch (std::exception& e)