net: davinci_emac: Fix incomplete code for getting the phy from device tree

Looks like the phy_id is never set up beyond getting the phandle.
Note that we can remove the ifdef for phy_node as there is a stub
for of_phy_connec() if CONFIG_OF is not set.

Cc: Brian Hutchinson <b.hutchman@gmail.com>
Cc: Felipe Balbi <balbi@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: David S. Miller <davem@davemloft.net>