bug#74196: maint: assume proper behavior of tolower

[Paul Eggert]

On 2024-11-11 10:42, Collin Funk wrote:
I doubt MSDOS, OS2, ATARI would be supported by Gnulib.

Not only are they not supported by Gnulib, I'm sure gzip hasn't worked 
on them for decades. We just haven't bothered to rip out all the 
supporting code.