drivers/mmc: correct error-handling code

Author: Julia Lawall <julia@diku.dk>

sdhci_alloc_host returns an ERR_PTR value in an error case instead of NULL.

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

// 
@match exists@
expression x, E;
statement S1, S2;
@@

x = sdhci_alloc_host(...)
... when != x = E
(
*  if (x == NULL || ...) S1 else S2
|
*  if (x == NULL && ...) S1 else S2
)
// 

Signed-off-by: Julia Lawall 
Acked-by: Anton Vorontsov 
Cc: Matt Fleming 
Cc: Ian Molton 
Cc: "Roberto A. Foglietta" 
Cc: Philip Langdale 
Cc: Pierre Ossman 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds 

---
 drivers/mmc/host/sdhci-of.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
 
diff --git a/drivers/mmc/host/sdhci-of.c b/drivers/mmc/host/sdhci-of.c
index 9088443..1e8aa590 100644
--- a/drivers/mmc/host/sdhci-of.c
+++ b/drivers/mmc/host/sdhci-of.c
@@ -234,7 +234,7 @@ static int __devinit sdhci_of_probe(struct of_device *ofdev,
 		return -ENODEV;
 
 	host = sdhci_alloc_host(&ofdev->dev, sizeof(*of_host));
-	if (!host)
+	if (IS_ERR(host))
 		return -ENOMEM;
 
 	of_host = sdhci_priv(host);