Test VPD read and write using vpd-tool

Added below test cases:
     - Verify System VPD
     - Verify VPD Component Read
     - Verify VPD Field Read
     - Verify VPD Field Write

Change-Id: I6c27758985c6820527a51f4f46728e2ea41c2008
Signed-off-by: Rahul Maheshwari <rahulmaheshwari@in.ibm.com>
diff --git a/data/vpd_variables.py b/data/vpd_variables.py
new file mode 100644
index 0000000..3512776
--- /dev/null
+++ b/data/vpd_variables.py
@@ -0,0 +1,29 @@
+#!/usr/bin/python
+
+r"""
+Contains VPD related constants.
+"""
+
+VPD_DETAILS = {
+    "/system/chassis/motherboard": {
+        "type": "xyz.openbmc_project.Inventory.Item.Board.Motherboard"
+    },
+    "/system/chassis/motherboard/base_op_panel_blyth": {
+        "type": "xyz.openbmc_project.Inventory.Item.Panel"
+    },
+    "/system/chassis/motherboard/ebmc_card_bmc": {
+        "type": "xyz.openbmc_project.Inventory.Item.Bmc"
+    },
+    "/system/chassis/motherboard/lcd_op_panel_hill": {
+        "type": "xyz.openbmc_project.Inventory.Item.Panel"
+    },
+    "/system/chassis/motherboard/tpm_wilson": {
+        "type": "xyz.openbmc_project.Inventory.Item.Tpm"
+    },
+    "/system/chassis/motherboard/vdd_vrm0": {
+        "type": "xyz.openbmc_project.Inventory.Item.Vrm"
+    },
+    "/system/chassis/motherboard/vdd_vrm1": {
+        "type": "xyz.openbmc_project.Inventory.Item.Vrm"
+    }
+}