net: dsa: mv88e6xxx: Correct spelling of define "ADRR" -> "ADDR"

Because ADRR is not a thing.

Signed-off-by: Tobias Waldekranz <tobias@waldekranz.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>