ARM: dts: aspeed: tacoma: Clean up KCS nodes

Make the Tacoma KCS nodes reflect the configuration of the Rainier and
Everest nodes.

Signed-off-by: Andrew Jeffery <andrew@aj.id.au>
Link: https://lore.kernel.org/r/20210709151119.2683600-1-andrew@aj.id.au


Signed-off-by: Joel Stanley <joel@jms.id.au>