[$] Removing the kthread freezer

The final day of the2023 Linux Storage, Filesystem,Memory-Management and BPF Summit featured three separate sessions led byLuis Chamberlain (he also led a plenary onday two); the first of those was a filesystem session on the status of thekthread-freezer-removal effort. The kthread freezer is meant to helpfilesystems freeze their state in order tosuspend or hibernate the system, but since at least2015, the freezer has been targeted for removal. Thingsdid not change much a year later, nor by LSFMM in2018 when Chamberlain had picked up Jiri Kosina's removaleffort; this year, Chamberlain was back to try to push things along.