Support legacy NFSv4 client tracking methods (DEPRECATED)

configname: CONFIG_NFSD_LEGACY_CLIENT_TRACKING

Linux Kernel Configuration
└─>File systems
└─>Network File Systems
└─>Support legacy NFSv4 client tracking methods (DEPRECATED)
In linux kernel since version 6.8 (release Date: 2024-03-10)  
The NFSv4 server needs to store a small amount of information on
stable storage in order to handle state recovery after reboot. Most
modern deployments upcall to a userland daemon for this (nfsdcld),
but older NFS servers may store information directly in a
recoverydir, or spawn a process directly using a usermodehelper
upcall.

These legacy client tracking methods have proven to be probelmatic
and will be removed in the future. Say Y here if you need support
for them in the interim.