Unused trace events in nfs and nfsd

[Steven Rostedt <rostedt@goodmis.org>]

I have code that will trigger a warning if a trace event is defined but
not used[1]. It gives a list of unused events. Here's what I have in nfs
and nfsd:

warning: tracepoint 'nfs4_renew' is unused.
warning: tracepoint 'nfs4_rename' is unused.
warning: tracepoint 'nfsd_file_unhash_and_queue' is unused.
warning: tracepoint 'nfsd_file_lru_add_disposed' is unused.
warning: tracepoint 'nfsd_file_lru_del_disposed' is unused.
warning: tracepoint 'nfsd_file_gc_recent' is unused.
warning: tracepoint 'nfsd_ctl_maxconn' is unused.

nfs4_renew looks to never have been used.

trace_nfs4_rename() was removed by 33912be816d9 ("nfs: remove
synchronous rename code") but did not remove the event.

trace_nfsd_file_unhash_and_queue() was removed by ac3a2585f01 ("nfsd:
rework refcounting in filecache")

Events nfsd_file_lru_add_disposed and nfsd_file_lru_del_disposed were
added by 4a0e73e635e3 ("NFSD: Leave open files out of the filecache
LRU") but they were never used.

Event nfsd_file_gc_recent was added by 64912122a4f8 ("nfsd: filecache:
introduce NFSD_FILE_RECENT") but never used.

trace_nfsd_ctl_maxconn() was removed by a4b853f183a1 ("sunrpc: remove
all connection limit configuration") but did not remove the event.

-- Steve

[1] https://lore.kernel.org/linux-trace-kernel/20250612235827.011358765@goodmis.org/