lists: drop luci-mod-admin-full from nas pkglist

This allows access to file browser in Luci but this is very limited access. There seems to be a problem with displaying files and there is no way to modify files at all so this is kind of useless. This is also not directly accessible trough Luci but you have to know specific URI to access it. This makes it probably just fully unknown to users so let's just drop it.