lang/php85: Update version 8.5.0alpha2=>8.5.0alpha3

• Remove opcache module as it is part of default php
• Remove www/php85-opcache
• Remove opcache module from lang/php85-extensions
• Indent Makefile properly

Please DO NOT use this version in production, it is an early test
version.

Changelog: https://github.com/php/php-src/blob/php-8.5.0alpha3/NEWS