[][openwrt][MT7981][switch][remove AN8855 image build]

[Description]
Remove AN8855 image build, using common SDK image instead

[Release-log]
N/A


Change-Id: I0ff6fbb04fcd274ab815764d2e2d378a5ffb33c0
Reviewed-on: https://gerrit.mediatek.inc/c/openwrt/feeds/mtk_openwrt_feeds/+/9250137
1 file changed