iio: temperature: ltc2983: Use single error path to put OF node

iio: temperature: ltc2983: Use single error path to put OF node

There are several, possibly copied'n'pasted, places in the functions,
where OF node is put and error returned directly, while the common
exit point exists. Unify all these cases to use a single error path.

Suggested-by: Jonathan Cameron <jic23@kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Nuno Sá <nuno.sa@analog.com>
Link: https://lore.kernel.org/r/20220307203606.87258-2-andriy.shevchenko@linux.intel.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>