Staging: ipack: fix wrong return value.

In case it is not possible to remap the memory, it returns 0 and
the driver thinks that everything went fine.
Signed-off-by: Samuel Iglesias Gonsalvez <siglesias@igalia.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/ipack/ipack.c

@@ -355,7 +355,7 @@ static int ipack_device_read_id(struct ipack_device *dev)
 			dev->region[IPACK_ID_SPACE].size);
 	if (!idmem) {
 		dev_err(&dev->dev, "error mapping memory\n");
-		return ret;
+		return -ENOMEM;
 	}
 
 	/* Determine ID PROM Data Format.  If we find the ids "IPAC" or "IPAH"