hostapd: add ubus bindings for wps

With this patch WPS discovery can be started or canceled over ubus if
WPS is enabled in wireless configuration. This is equivalent of
'hostapd_cli wps_pbc' and 'hostapd_cli wps_cancel' commands.

Signed-off-by: Petar Koretic <petar.koretic@sartura.hr>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@42459 3c298f89-4303-0410-b956-a3cf2f4a3e73
atheros: enable the low_mem flag to better deal with 16M RAM devices

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@42460 3c298f89-4303-0410-b956-a3cf2f4a3e73
kernel: remove unused versions

Signed-off-by: Luka Perkov <luka@openwrt.org>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@42462 3c298f89-4303-0410-b956-a3cf2f4a3e73