iio: pressure: bmp280: Add nvmem operations for BMP580

The pressure sensor BMP580 contains a non-volatile memory that stores
trimming and configuration params. That memory provides an programmable
user range of three 2-byte words.

Signed-off-by: Angel Iglesias <ang.iglesiasg@gmail.com>
Link: https://lore.kernel.org/r/f3f453d9b2c0f7820ca9c56e24e2165b6c39bb67.1676823250.git.ang.iglesiasg@gmail.com


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