net: bcmgenet: Use devm_ioremap_resource()

According to Documentation/driver-model/devres.txt, devm_request_and_ioremap()
is deprecated, so use devm_ioremap_resource() instead.

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>