net/phpldapadmin: add patches to support php84

net/phpldapadmin (version 1) was written some years ago. The developer
of PLA (https://github.com/leenooks/phpLDAPadmin) officially dropped
support for PLA1, but PLA2 is still not full functional as PLA1.

I've made small patches which enable support for php84 (changes of some
builtin php functions, declarations of variables and so on).

With these patches PLA1 (still) is working corectly.

PR: 287238
Event: Wiesbaden Hackathon 202604
(cherry picked from commit d4a83eff40d6515ddb6fca3c1bbb780a9747be28)