Update ProcNetSOFTNETSTAT handler and CSV/JSON verification files

There's a new field in the file in later kernels, so the handler needs
to be able to handle either format.  Also, since the fields changed the
pre-generated JSON/CSV files used by the verification scripts needed
to be updates as well.
/proc/net/softnet_stat recreator can handle new/optional field now.
'recreate-proc-file' ignored unsupported file now