Specify the switch ports in the DTS file.
Re-enable it after it was disabled by commit e9672b1a8f ("bcm53xx: switch to the
upstream DSA-based b53 driver").
Signed-off-by: SHIMAMOTO Takayoshi <takayoshi.shimamoto.360@gmail.com>
[rmilecki: reword commit & drop unneeded whitespace change]
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>