programs/README.md: update help text
programs/README.md: update help text

I noticed that the help is outdated as there is no mention of --adapt. Y'all should probably put "update help text" into your release checklist.
Cyan4973/zstd,Cyan4973/zstd,Cyan4973/zstd,Cyan4973/zstd,Cyan4973/zstd