php: enable mysql extension on --with-mariadb
php: enable mysql extension on --with-mariadb

Closes #129.

Signed-off-by: Jack Nagel <43386ce32af96f5c56f2a88e458cb94cebee3751@gmail.com>

mkalkbrenner/homebrew-php,TomK/homebrew-php,philcook/homebrew-php,ablyler/homebrew-php,dguyon/homebrew-php