I have drupal running perfectly; with mysql support. But CiviCRM still giving me this error - “MySQL support not included in PHP.”
My PHP version is 5.6.31, as indicated in the screenshot below.
Your drupal may be using a different mysql driver. CiviCRM recently migrated to requiring mysqli. See https://civicrm.org/blog/totten/psa-please-verify-php-extension-mysqli for more details.