iio:magnetometer: st_magn: add LSM9DS1 support

Update the sensor settings to support the LSM9DS1 sensor. Although the
LSM9DS1 accelerometer and gyroscope are coupled together to use the same
FIFO, the magnetometer is separate and can be cleanly supported without
refactoring the existing driver.

Signed-off-by: Martin Kelly <martin@martingkelly.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
2 jobs for imx8-4.18-wip in 42 minutes and 29 seconds (queued for 1 second)
Status Job ID Name Coverage
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passed #10993
librem5
build:aarch64:Image

00:42:29

passed #10994
librem5
build:aarch64:deb

00:28:14