Validate the mac address during set

Allow the mac to be set if one of the condition is true.
1) Incoming Mac is of local admin type.
        or
2) Incoming mac is same as eeprom Mac.

Fixes openbmc/openbmc#622

Change-Id: I4289b18b8460d56cf9956b7c3028da6468f27974
Signed-off-by: Ratan Gupta <ratagupt@in.ibm.com>
diff --git a/conf/network-manager.conf b/conf/network-manager.conf
new file mode 100644
index 0000000..2f85cec
--- /dev/null
+++ b/conf/network-manager.conf
@@ -0,0 +1,5 @@
+[mac_loc]
+path=/org/openbmc/inventory/system/chassis/io_board
+bus=org.openbmc.Inventory
+interface=org.openbmc.InventoryItem
+property=Custom Field 2