drivers/staging/crystalhd/crystalhd_lnx.c: adjust inconsistent IS_ERR and PTR_ERR

Change the call to PTR_ERR to access the value just tested by IS_ERR.

The semantic match that finds this problem is as follows:
(http://coccinelle.lip6.fr/)

// <smpl>
@@
expression e,e1;
@@

(
if (IS_ERR(e)) { ... PTR_ERR(e) ... }
|
if (IS_ERR(e=e1)) { ... PTR_ERR(e) ... }
|
*if (IS_ERR(e))
 { ...
*  PTR_ERR(e1)
   ... }
)
// </smpl>

Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/crystalhd/crystalhd_lnx.c

@@ -381,7 +381,7 @@ static int __devinit chd_dec_init_chdev(struct crystalhd_adp *adp)
 	dev = device_create(crystalhd_class, NULL, MKDEV(adp->chd_dec_major, 0),
 			    NULL, "crystalhd");
 	if (IS_ERR(dev)) {
-		rc = PTR_ERR(crystalhd_class);
+		rc = PTR_ERR(dev);
 		BCMLOG_ERR("failed to create device\n");
 		goto device_create_fail;
 	}