POSIX: add changelog entries for PHP 8.5 changes

[lacatoire]

PHP 8.5 brings several POSIX changes already documented in
`appendices/migration85` but missing from the per-function changelogs.

• posix_kill: ValueError on out-of-range process_id
• posix_setpgid: ValueError on out-of-range process_id/process_group_id
• posix_setrlimit: ValueError on invalid hard_limit/soft_limit
• posix_ttyname: last_error EBADF on invalid file_descriptor
• posix_isatty: E_WARNING on invalid file_descriptor
• posix_fpathconf: last_error EBADF + E_WARNING on invalid file_descriptor

Same spirit as #5528.

[lacatoire]

same as #5528 @jordikroon

[jordikroon]

I will get to this in a moment, but please be patient as I am also looking after a few older MR's.

[jordikroon]

The following 8.5 change also needs to be documented.

posix_setpgid throws a ValueError when the process_id or
the process_group_id is lower than zero or greater than
what the platform supports.

[jordikroon]

The following 8.5 change also needs to be documented.

posix_setpgid throws a ValueError when the process_id or
the process_group_id is lower than zero or greater than
what the platform supports.

@lacatoire would you be willing to document the posix_setpgid change as well?

[lacatoire]

The following 8.5 change also needs to be documented.

posix_setpgid throws a ValueError when the process_id or
the process_group_id is lower than zero or greater than
what the platform supports.

@lacatoire would you be willing to document the posix_setpgid change as well?

You mean there ?

[jordikroon]

Yep.. That one completely slipped my brain. Thanks!