correct the name of Inventory.Item.Bmc interface

As defined in the PDIs [1], the correct name of this interface is
Inventory.Item.Bmc (not BMC). This commit corrects all configuration
that are using incorrect interface name.

[1] https://github.com/openbmc/phosphor-dbus-interfaces/blob/master/yaml/xyz/openbmc_project/Inventory/Item/Bmc.interface.yaml

Change-Id: Icc9b4b33725999a72cd925fd0f0e5995aacadcdc
Signed-off-by: Thang Tran <thuutran@amperecomputing.com>
diff --git a/configurations/mtmitchell_bmc.json b/configurations/mtmitchell_bmc.json
index 227d78f..8ca8b8f 100644
--- a/configurations/mtmitchell_bmc.json
+++ b/configurations/mtmitchell_bmc.json
@@ -128,7 +128,7 @@
         "FieldReplaceable": false,
         "HotPluggable": false
     },
-    "xyz.openbmc_project.Inventory.Item.BMC": {},
+    "xyz.openbmc_project.Inventory.Item.Bmc": {},
     "xyz.openbmc_project.Inventory.Item.NetworkInterface": {
         "MACAddress": "$BOARD_INFO_AM1"
     }