Fix #70103: Fix bug 70103 when ZTS is enabled

[mhagstrand]

Used snprintf to copy the basename string before it is freed

========DIFF========
002+ string(6) "hp-src"
002- string(7) "foo.txt"
========DONE========
FAIL Bug #70103 (ZipArchive::addGlob ignores remove_all_path option) [ext/zip/tests/bug70103.phpt] 

https://travis-ci.org/php/php-src/jobs/189428235

[mhagstrand]

@cmb69 Can you take a look at the change since this is a change to your fix on #1430

[cmb69]

Good catch, Mitch. Thanks! I'm going to merge this PR.

[cmb69]

@krakjoe This PR is not testing related, but rather fixes a use after free which my recently merged PR #1430 introduced.

[krakjoe]

@cmb69 and I knew that, because I read it ... fingers are faster than brain sometimes :D

ta ...

[php-pulls]

Comment on behalf of cmb at php.net:

Applied with commit ad08aa3.