rtl838x: fine tune default package set
Althought most of the switches aren't routers, they can be used as such,
so let's add some of the packages from the router's DEVICE_TYPE. While
at it, remove swconfig package which is not needed on DSA targets.
Acked-by: John Crispin <[email protected]>
Signed-off-by: Petr Štetiar <[email protected]>