net: lwip: remove eth_init from net_init as it is called later

net: lwip: remove eth_init from net_init as it is called later

The call to eth_init within net_init causes the network interface to
start, stop, start again which can cause issues with certain network
device drivers. Remove it to make it behave like the legacy network
path.

Fixes: 5666865decb8 ("net: lwip: fix initialization sequence before a command")
Signed-off-by: Tim Harvey <tharvey@gateworks.com>
Reviewed-by: Jerome Forissier <jerome.forissier@linaro.org>