Plugins are built as shared libraries and are therefore installed into
$libdir/bind. Meanwhile, the build system sets the NAMED_PLUGINDIR
preprocessor variable to $datadir/bind instead. This prevents loading
plugins specified in the configuration file using just the shared
library name (i.e. without using an absolute path or a relative path).
Fix by setting NAMED_PLUGINDIR to the path that plugins are actually
installed into.
config.set_quoted('RNDC_CONFFILE', sysconfdir / 'rndc.conf')
config.set_quoted('RNDC_KEYFILE', sysconfdir / 'rndc.key')
-config.set_quoted('NAMED_PLUGINDIR', datadir / 'bind')
+config.set_quoted('NAMED_PLUGINDIR', libdir / 'bind')
config.set_quoted('NAMED_LOCALSTATEDIR', localstatedir)
config.set_quoted('NAMED_SYSCONFDIR', sysconfdir)
config.set_quoted('NAMED_CONFFILE', sysconfdir / 'named.conf')