Also the readline and libedit options are mutually exclusive, so you cannot enable both at the same time. If one is enabled the other is disabled.
Permanent global pkg build options can be defined via 'XBPS_PKG_OPTIONS' in etc/conf. Permament per-pkg build options can be defined via 'XBPS_PKG_OPTIONS_<pkgname>' in etc/conf. Close GH #452.