brcmfmac: fix reporting support for 160 MHz channels

Driver can report IEEE80211_VHT_CAP_SUPP_CHAN_WIDTH_160MHZ so it's
important to provide valid & complete info about supported bands for
each channel. By default no support for 160 MHz should be assumed unless
firmware reports it for a given channel later.

This fixes info passed to the userspace. Without that change userspace
could try to use invalid channel and fail to start an interface.

Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Cc: stable@vger.kernel.org
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>