mtd/maps/pismo: remove dangling pointer and a leak

While looking for drivers which forgot to clear i2c_clientdata before freeing
the data structure it points to, I found that the pismo driver even has a leak
on the probe error path.

Signed-off-by: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
diff --git a/drivers/mtd/maps/pismo.c b/drivers/mtd/maps/pismo.c
index c48cad2..0a5e243 100644
--- a/drivers/mtd/maps/pismo.c
+++ b/drivers/mtd/maps/pismo.c
@@ -233,6 +233,7 @@
 	/* FIXME: set_vpp needs saner arguments */
 	pismo_setvpp_remove_fix(pismo);
 
+	i2c_set_clientdata(client, NULL);
 	kfree(pismo);
 
 	return 0;
@@ -271,7 +272,7 @@
 	ret = pismo_eeprom_read(client, &eeprom, 0, sizeof(eeprom));
 	if (ret < 0) {
 		dev_err(&client->dev, "error reading EEPROM: %d\n", ret);
-		return ret;
+		goto exit_free;
 	}
 
 	dev_info(&client->dev, "%.15s board found\n", eeprom.board);
@@ -282,6 +283,11 @@
 				      pdata->cs_addrs[i]);
 
 	return 0;
+
+ exit_free:
+	i2c_set_clientdata(client, NULL);
+	kfree(pismo);
+	return ret;
 }
 
 static const struct i2c_device_id pismo_id[] = {