crypto: crypto4xx - fix error return code

Convert a nonnegative error return code to a negative one, as returned
elsewhere in the function.

A simplified version of the semantic match that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
(
if@p1 (\(ret < 0\|ret != 0\))
 { ... return ret; }
|
ret@p1 = 0
)
... when != ret = e1
    when != &ret
*if(...)
{
  ... when != ret = e2
      when forall
 return ret;
}
// </smpl>

Signed-off-by: Peter Senna Tschudin <peter.senna@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

drivers/crypto/amcc/crypto4xx_core.c

@@ -1226,6 +1226,7 @@ static int __init crypto4xx_probe(struct platform_device *ofdev)
 	core_dev->dev->ce_base = of_iomap(ofdev->dev.of_node, 0);
 	if (!core_dev->dev->ce_base) {
 		dev_err(dev, "failed to of_iomap\n");
+		rc = -ENOMEM;
 		goto err_iomap;
 	}