Don't select channels designated for exclusive-indoor use when the
country3 element is set on outdoor operation.

This effectively prevents from using indoor-only channels in case
outdoor-mode is activated. It can be seen as a safeguard from selecting
inapprpriate channels in a site outdoor-chanlist.

Signed-off-by: David Bauer <mail@david-bauer.net>

Signed-off-by: David Bauer <mail@david-bauer.net>