brcm80211: smac: don't validate channels against internal regulatory …

…data

The core regulatory support will disable channels not allowed by
regulatory rules, so brcmsmac doesn't need to check whether or not the
requested channel is permitted by regulatory.

Reviewed-by: Arend Van Spriel <arend@broadcom.com>
Reviewed-by: Pieter-Paul Giesberts <pieterpg@broadcom.com>
Signed-off-by: Seth Forshee <seth.forshee@canonical.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>