eth_v10: Removing dead ETRAX_NETWORK_RED_ON_NO_CONNECTION

ETRAX_NETWORK_RED_ON_NO_CONNECTION doesn't exist in Kconfig, therefore
removing all references for it from the source code.

Signed-off-by: Christoph Egger <siccegge@cs.fau.de>
Signed-off-by: David S. Miller <davem@davemloft.net>