net: phy: fix a bug when verify the EEE support

The phy_init_eee has to exit with an error when the
local device and its link partner both do not support EEE.
So this patch fixes a problem when verify this.

Signed-off-by: Giuseppe Cavallaro <peppe.cavallaro@st.com>
Signed-off-by: David S. Miller <davem@davemloft.net>