iio: Switch i2c drivers back to use .probe()

After commit b8a1a4cd5a98 ("i2c: Provide a temporary .probe_new()
call-back type"), all drivers being converted to .probe_new() and then
03c835f498b5 ("i2c: Switch .probe() to not take an id parameter") convert
back to (the new) .probe() to be able to eventually drop .probe_new() from
struct i2c_driver.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230515205048.19561-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: ti-ads1100: fix error code in probe()

This code has a copy and paste bug so it accidentally returns
"PTR_ERR(data->reg_vdd)" which is a valid pointer cast to int. It
should return "ret" instead.

Fixes: 541880542f2b ("iio: adc: Add TI ADS1100 and ADS1000")
Signed-off-by: Dan Carpenter <error27@gmail.com>
Link: https://lore.kernel.org/r/36fa2aeb-f392-4793-8b38-ae15514033c8@kili.mountain
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

iio: adc: Add TI ADS1100 and ADS1000

The ADS1100 is a 16-bit ADC (at 8 samples per second).
The ADS1000 is similar, but has a fixed data rate.

Signed-off-by: Mike Looijmans <mike.looijmans@topic.nl>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20230307065535.7927-2-mike.looijmans@topic.nl
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>