Add -z flag in phpdbg output (#9669)

[adsr]

Flag is already present in man page.

(Requesting hacktoberfest-accepted label for Hacktoberfest cred.)

[nielsdos]

I don't know whether you're still interested in getting this merged, but:
It mostly looks good, except on Windows: there the PHP_SHLIB_SUFFIX is "dll", which is one character longer than "so". So there the help overview line for -z will have a space too many which unaligns the column. You could fix this by defining an additional macro in phpdbg_help.c based on PHP_SHLIB_SUFFIX to take into account the spacing.

Edit: ah and it's even different for macos, you might want to check how other SAPIs do this.

[adsr]

Removed lib extension to ensure consistent formatting. Alternatives are too much complexity for too little benefit IMO.

[nielsdos]

Alternatives are too much complexity for too little benefit IMO.

I agree.

php --help gives:
-z <file> Load Zend extension <file>.

Perhaps it could be made consistent to that. Either I can do that or you can change the commit. Let me know :)

EDIT: actually this looks fine because it's talking about an example, I'm merging.

[nielsdos]

Merged into 8.1 and above, thanks!