net: sun8i_emac: Fix PHY initialization

The previous code tried to update the PHY parameters without waiting for
autonegotiation to complete. This caused wrong values to be written to
the EMAC in sun8i_adjust_link(). As a result, any commands that called
eth_start() before autonegotiation completed would find the network
nonfunctional. Fix this by using the correct function to start up the
PHY.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Acked-by: Joe Hershberger <joe.hershberger@ni.com>
Reviewed-by: Jagan Teki <jagan@openedev.com>