ProductId: remove property

At both the top-level and in Item.Board.Motherboard schemas was a
required property: "ProductId".  This property has never been documented
in phosphor-dbus-interfaces and is only used in exactly 1 OEM IPMI
provider (and no where else)[1, 2].  Strip this unused property out.

Test Plan: entity-manager schema validators pass.  Search in code base
for usages.

[1]: https://github.com/openbmc/intel-ipmi-oem/blob/0fcc73f1cf8c486bb8079e68813c239c4cc41bbc/src/oemcommands.cpp#L2929
[2]: https://github.com/search?q=org%3Aopenbmc+%2F%28%3F-i%29ProductId%2F+-repo%3Aopenbmc%2Flinux+-repo%3Aopenbmc%2Fqemu&type=code

Signed-off-by: Patrick Williams <patrick@stwcx.xyz>
Change-Id: I81f02c54aaee78e5d1c3b3e020437ebd3d7b4e3f
diff --git a/configurations/wft_baseboard.json b/configurations/wft_baseboard.json
index 992673a..845ccdf 100644
--- a/configurations/wft_baseboard.json
+++ b/configurations/wft_baseboard.json
@@ -1632,8 +1632,6 @@
     "xyz.openbmc_project.Inventory.Decorator.AssetTag": {
         "AssetTag": "$PRODUCT_ASSET_TAG"
     },
-    "xyz.openbmc_project.Inventory.Item.Board.Motherboard": {
-        "ProductId": 123
-    },
+    "xyz.openbmc_project.Inventory.Item.Board.Motherboard": {},
     "xyz.openbmc_project.Inventory.Item.System": {}
 }