Enable sku on BPi-R4 after device rebooted, remove bad patch and update
defconfigs.

To control txpower from UCI config we need to enable SKU. It is done via updating file with 0 instead of 1 and allow to use sku_idx in UCI configuration to control txpower. This file is restored after reboot so need to run that on each reboot.

Remove hostapd patch since WEP is working without it on BPI.

Add openwrtuser in Docker to build under it. This is required to pass a
HASH check of hostpad. HASH is different if builded under root.

BUG=b/526492296
TEST=./scripts/BananaPi-R4.sh

Change-Id: I660963a89f0698db7fc939e8945407d7c9ab3f34
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/dev-util/+/7967606
Reviewed-by: Jason Stanko <jstanko@google.com>
Tested-by: Alexandr Astrouski <astrouski@google.com>
Commit-Queue: Alexandr Astrouski <astrouski@google.com>