drivers/misc/carma/carma-fpga.c: use PTR_ERR_OR_ZERO

replace IS_ERR/PTR_ERR

Cc: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <robh+dt@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Fabian Frederick <fabf@skynet.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/misc/carma/carma-fpga.c

@@ -954,10 +954,7 @@ static int data_debugfs_init(struct fpga_device *priv)
 {
 	priv->dbg_entry = debugfs_create_file(drv_name, S_IRUGO, NULL, priv,
 					      &data_debug_fops);
-	if (IS_ERR(priv->dbg_entry))
-		return PTR_ERR(priv->dbg_entry);
-
-	return 0;
+	return PTR_ERR_OR_ZERO(priv->dbg_entry);
 }
 
 static void data_debugfs_exit(struct fpga_device *priv)