iio: magnetometer: yas530: Add temperature calculation to "chip_info"

Add temperature calculation to the "chip_info" structure to ease the handling
of different YAS variants.

Signed-off-by: Jakob Hauser <jahau@rocketmail.com>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/1a8bffdb7e807455620a73f2d61981e7f9aab8d5.1660337264.git.jahau@rocketmail.com


Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>