Completely disable dump_survey code on ARCH_BCM2835 to fix defined but not
used warning.
512b762ddb (commitcomment-137899352)
Fixes: 512b762ddbb6 ("mac80211: brcm: disable dump_survey on Raspberry Pi")
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
Enabling this causes slow iwinfo calls on Raspberry Pi and LuCI slows down
when wireless is enabled.
Fixes: https://github.com/openwrt/openwrt/issues/14013
Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>