The USES= fragments are not supposed to modify OPTIONS_* because they are
loaded after bsd.options.mk.
In the particular case of drupal, this resulted in SELECTED_OPTIONS and
DESELECTED_OPTIONS being incorrect. A second problem was that the "="
was used for assignment rather than "?=", meaning that any port with
USES=drupal got their options overwritten at some point (this included
the main www/drupal6 and www/drupal7 ports).
This commit adds OPTIONS_DEFINE=DOCS to almost every port that had set
USES=drupal to correct the mistake of setting options in Mk/Uses.
PR: 206060