dt-bindings: iio: st,st-sensors add LIS302DL

Update st,st-sensors bindings for STMicroelectronics LIS302DL variant

Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Sicelo A. Mhlongo <absicsz@gmail.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://lore.kernel.org/r/20220307132502.73854-2-absicsz@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>