vpd:Create default error interface

This commit creates a default error type for VPD related
errors. When no specific error type is matching, this
default error type can be published in error logs.

Change-Id: I80e368f2aeda90b18d0243644ac133c54c102141
Signed-off-by: Priyanga Ramasamy <[email protected]>

Author: PriyangaRamasamy

yaml/com/ibm/VPD.errors.yaml

@@ -28,3 +28,6 @@
       Could not determine which device tree to switch to, as system type is
       unknown. Please check the HW and  IM keywords in the system VPD and check
       if they are programmed correctly.
+- name: DefaultError
+  description:
+      Error processing the VPD request. This can be used as a default error type.