mac80211: initialize sta->last_rx in sta_info_alloc

This field is used to determine the inactivity time. When in AP mode,
hostapd uses it for kicking out inactive clients after a while. Without this
patch, hostapd immediately deauthenticates a new client if it checks the
inactivity time before the client sends its first data frame.

Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Cc: stable@kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index 5a11078..d0311a3 100644
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -243,6 +243,7 @@
 	memcpy(sta->sta.addr, addr, ETH_ALEN);
 	sta->local = local;
 	sta->sdata = sdata;
+	sta->last_rx = jiffies;
 
 	ewma_init(&sta->avg_signal, 1024, 8);