iio: magnetometer: ak8974: remove redundant zero timeout check

At the end of the delay loop timeout will always be zero
and hence the check for !timeout will always be true. Remove
the redundant check and the redundant return 0 at the end of
the function.

Fixes CoverityScan CID#1357168 ("Logically dead code")
Signed-off-by: NColin Ian King <colin.king@canonical.com>
Reviewed-by: NLinus Walleij <linus.walleij@linaro.org>
Signed-off-by: NJonathan Cameron <jic23@kernel.org>

drivers/iio/magnetometer/ak8974.c

@@ -278,13 +278,9 @@ static int ak8974_await_drdy(struct ak8974 *ak8974)
 		if (val & AK8974_STATUS_DRDY)
 			return 0;
 	} while (--timeout);
-	if (!timeout) {
-		dev_err(&ak8974->i2c->dev,
-			"timeout waiting for DRDY\n");
-		return -ETIMEDOUT;
-	}
 
-	return 0;
+	dev_err(&ak8974->i2c->dev, "timeout waiting for DRDY\n");
+	return -ETIMEDOUT;
 }
 
 static int ak8974_getresult(struct ak8974 *ak8974, __le16 *result)