bug#65423: README-install contains invalid/outdated information about 32 bit time_t compared to NEWS in 9.3

[Osipov, Michael (IN IT IN)]

Folks,

in 9.3 year 2038 support with 64 bit time_t was made required [1], here 
on HP-UX this is a bit problematic, but that's not the actual problem. 
The diff between 9.2 and 9.3 [2] says how this can be fixed on platforms 
supporting both 32 and 64 bit, on HP-UX it'd be simply '+DD64', and how 
to avoid with "ac_year2038_required=no", but README-install on master 
[3] still contains '--disable-year2038' which obviously does not work. 
It simply needs to be updated to the content of [2].

FTR: I cannot compile everything in 64 bit mode since no one has written 
our old applications with portability in mind. It needs to remain 32 bit 
for now.

Michael

[1] 
https://github.com/coreutils/coreutils/commit/ffd62ab92c259d513a419b4078a45f1c658dc774
[2] 
https://github.com/coreutils/coreutils/compare/v9.2...v9.3#diff-2646d31b27172b7564edd6b4e2116efd8ee5c0cb5355129e8ef9b53ed0ea01b4
[3] 
https://github.com/coreutils/coreutils/blob/20b9a015e5aa05c6ad58bda8e9fa963d217b05e3/README-install#L53-L63