package/php-xdebug: add zlib optional dependency
zlib is an optional dependency (enabled by default) since bump to
version 3.2.0 in commit 8280400fbadde09e51ccff312d7a4ef6a386f589 and
https://github.com/xdebug/xdebug/commit/3954e5cd9e48eec0a8a2a0c6a2fc120bbe562656
Fixes: 8280400fbadde09e51ccff312d7a4ef6a386f589
Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
(cherry picked from commit 4b7aeee28ed2f62370084dac4a92bdef89046b41)
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>