sh_eth: use SET_RUNTIME_PM_OPS()

Use SET_RUNTIME_PM_OPS() macro to initialize the runtime PM method pointers in
the 'struct dev_pm_ops'.

Signed-off-by: Mikhail Ulyanov <mikhail.ulyanov@cogentembedded.com>
[Sergei: renamed, added the changelog.]
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: David S. Miller <davem@davemloft.net>