Add support for the Lunzn FastRhino R66S board.
Tested-by: Francisco G Luna <frangonlun@gmail.com>
Signed-off-by: Tianling Shen <cnsztl@immortalwrt.org>
Link: https://github.com/openwrt/openwrt/pull/19990
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>