brcmfmac: disable dump_survey on Raspberry Pi

Enabling this causes slow iwinfo calls on Raspberry Pi and LuCI slows down
when wireless is enabled.
https://github.com/openwrt/openwrt/issues/14013

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>
---

--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
@@ -8361,8 +8361,10 @@ struct brcmf_cfg80211_info *brcmf_cfg802
 	if (brcmf_feat_is_enabled(ifp, BRCMF_FEAT_WOWL_GTK))
 		ops->set_rekey_data = brcmf_cfg80211_set_rekey_data;
 #endif
+#if !defined(CONFIG_ARCH_BCM2835)
 	if (brcmf_feat_is_enabled(ifp, BRCMF_FEAT_DUMP_OBSS))
 		ops->dump_survey = brcmf_cfg80211_dump_survey;
+#endif /* CONFIG_ARCH_BCM2835 */
 
 	err = wiphy_register(wiphy);
 	if (err < 0) {