fix compile warning

fix compile warning: enumeration value not handled in switch in pbnjson::ErrorToSchemaError function

[GF-3986] pbnjson compile warning
Open-webOS-DCO-1.0-Signed-off-by: seokjun.lee <sseokjun.lee@lge.com>

Change-Id: Ife5b8316383ff55f3908411287dc2f3e191b9098