[PATCH] hw_features: provide proper fallback to HT20 by defering channel pair check

[Eduardo Abinader]

As hostapd currently allows some flexibility (fallback to ht20) on
setting channel to channel 20MHz, although ht40+/- has been initially
configured.
This patch just extends such flexibility. That said, ch165 fcc would
be then supported.
Doesn´t that make sense to allow such flexibility?

Thanks