net: systemport: Use devm_ioremap_resource()

Use devm_ioremap_resource() because devm_request_and_ioremap() is
obsoleted by devm_ioremap_resource().

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>