phy:icplus:fix Auto Power Saving in ip101a_config_init.

[ Upstream commit b3300146aa8efc5d3937fd33f3cfdc580a3843bc ]

This patch fixes Auto Power Saving configuration in ip101a_config_init
which was broken as there is no phy register write followed after
setting IP101A_APS_ON flag.

This patch also fixes the return value of ip101a_config_init.

Without this patch ip101a_config_init returns 2 which is not an error
accroding to IS_ERR and the mac driver will continue accessing 2 as
valid pointer to phy_dev resulting in memory fault.

Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>