'rc' is known to be 0 at this point.
If 'platform_get_resource()' or 'devm_ioremap()' fail, return -ENOMEM
instead of 0 which means success.

tj: Changed error code from -ENOMEM to -ENODEV for get_resource
    failure as suggested by Sergei.
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>