[PATCH] I2C: refactor message in i2c_detach_client

We could refactor the error message 34 different i2c drivers print if
i2c_detach_client() fails in this function itself. Saves quite a few
lines of code. Documentation is updated to reflect that change.

Note that this patch should be applied after Rudolf Marek's w83792d
patches.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/drivers/i2c/chips/pca9539.c b/drivers/i2c/chips/pca9539.c
index c5b0523..1500b18 100644
--- a/drivers/i2c/chips/pca9539.c
+++ b/drivers/i2c/chips/pca9539.c
@@ -163,10 +163,8 @@
 {
 	int err;
 
-	if ((err = i2c_detach_client(client))) {
-		dev_err(&client->dev, "Client deregistration failed.\n");
+	if ((err = i2c_detach_client(client)))
 		return err;
-	}
 
 	kfree(i2c_get_clientdata(client));
 	return 0;