base-files: wifi: swap the order of some ubus calls

base-files: wifi:  swap the order of some ubus calls

"/sbin/wifi up" makes three ubus calls:
1. ubus call network reload
2. ubus call network.wireless down
3. ubus call network.wireless up

The first and third ubus calls call drv_mac80211_setup,
while the second ubus call triggers wireless_device_setup_cancel,
so the call sequence becomes,

1. drv_mac80211_setup
2. wireless_device_setup_cancel
3. drv_mac80211_setup

This commit swaps the order of the first two ubus calls,
1. ubus call network.wireless down
2. ubus call network reload
3. ubus call network.wireless up

Consequently drv_mac80211_setup is only called once,
and two related bugs (#FS3784 and #FS3902) are no longer triggered
by /sbin/wifi.

branches affected: trunk, 21.02

Signed-off-by: Bob Cantor <coxede6557@w3boats.com>