I strongly recommend against placing additional files inside NiFi's lib directory. You should create a separate directory such as C:\NiFi\config-resources\ where you place and support files such as your hdfs-site.xml and core-site.xml files you reference in the PutHDFS processor. You just need to make sure the full directory path and the xml files are accessible by the user that is running the NiFi process.
As far as Kerberos Principal and Keytab properties go.... If you HDFS has been kerberized, you will need to create a service keytab/principal for the user running the NiFi service. This user must also be authorized in HDFS to access to target directory path you are trying to put files in.