offchannel: Use wpas_get_tx_interface() src parameter more consistently

Both the wpa_s->pending_action_src and src argument to
wpas_get_tx_interface() were used somewhat randomly. Make this more
consistent since these values are pointing to the same address and the
implementation is easier to understand when it is obvious that there is
only one address being used.

Signed-off-by: Jouni Malinen <j@w1.fi>

wpa_supplicant/offchannel.c

@@ -30,8 +30,7 @@ wpas_get_tx_interface(struct wpa_supplicant *wpa_s, const u8 *src)
 	 */
 	iface = wpa_s->global->ifaces;
 	while (iface) {
-		if (os_memcmp(wpa_s->pending_action_src,
-			      iface->own_addr, ETH_ALEN) == 0)
+		if (os_memcmp(src, iface->own_addr, ETH_ALEN) == 0)
 			break;
 		iface = iface->next;
 	}
@@ -265,8 +264,7 @@ int offchannel_send_action(struct wpa_supplicant *wpa_s, unsigned int freq,
 		struct wpa_supplicant *iface;
 		int ret;
 
-		iface = wpas_get_tx_interface(wpa_s,
-					      wpa_s->pending_action_src);
+		iface = wpas_get_tx_interface(wpa_s, src);
 		wpa_s->action_tx_wait_time = wait_time;
 
 		ret = wpa_drv_send_action(