crypto: dcp - Use devm_ioremap_resource()

Using devm_ioremap_resource() can make the code simpler and smaller.

When devm_ioremap_resource() is used there is no need to explicitely check the
error returned by platform_get_resource().

Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>