LogRedacting panics on nil value logging

[aloknnikhil]

With the new log redaction feature, we are seeing crashes in the logger when one of the values to be logged is nil

Example:

log.Debugf("RetrieveInterfaceStatusFromRamCache: %+v", ifStatus)

This panics if ifStatus is a pointer and is nil. It's completely valid in some cases to have a "nil" printed to the log.

[ondrej-fabry]

Please post the panic output with stack trace.