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 <[e-mail]>
Signed-off-by: Jonathan Cameron <[e-mail]>

drivers/iio/magnetometer/st_magn.h

···
 #define LIS3MDL_MAGN_DEV_NAME		"lis3mdl"
 #define LSM303AGR_MAGN_DEV_NAME		"lsm303agr_magn"
 #define LIS2MDL_MAGN_DEV_NAME		"lis2mdl"
+#define LSM9DS1_MAGN_DEV_NAME		"lsm9ds1_magn"
 
 int st_magn_common_probe(struct iio_dev *indio_dev);
 void st_magn_common_remove(struct iio_dev *indio_dev);

drivers/iio/magnetometer/st_magn_core.c

···
 		.wai_addr = ST_SENSORS_DEFAULT_WAI_ADDRESS,
 		.sensors_supported = {
 			[0] = LIS3MDL_MAGN_DEV_NAME,
+			[1] = LSM9DS1_MAGN_DEV_NAME,
 		},
 		.ch = (struct iio_chan_spec *)st_magn_2_16bit_channels,
 		.odr = {

drivers/iio/magnetometer/st_magn_i2c.c

···
 		.compatible = "st,lis2mdl",
 		.data = LIS2MDL_MAGN_DEV_NAME,
 	},
+	{
+		.compatible = "st,lsm9ds1-magn",
+		.data = LSM9DS1_MAGN_DEV_NAME,
+	},
 	{},
 };
 MODULE_DEVICE_TABLE(of, st_magn_of_match);
···
 	{ LIS3MDL_MAGN_DEV_NAME },
 	{ LSM303AGR_MAGN_DEV_NAME },
 	{ LIS2MDL_MAGN_DEV_NAME },
+	{ LSM9DS1_MAGN_DEV_NAME },
 	{},
 };
 MODULE_DEVICE_TABLE(i2c, st_magn_id_table);

drivers/iio/magnetometer/st_magn_spi.c

···
 		.compatible = "st,lis2mdl",
 		.data = LIS2MDL_MAGN_DEV_NAME,
 	},
+	{
+		.compatible = "st,lsm9ds1-magn",
+		.data = LSM9DS1_MAGN_DEV_NAME,
+	},
 	{}
 };
 MODULE_DEVICE_TABLE(of, st_magn_of_match);
···
 	{ LIS3MDL_MAGN_DEV_NAME },
 	{ LSM303AGR_MAGN_DEV_NAME },
 	{ LIS2MDL_MAGN_DEV_NAME },
+	{ LSM9DS1_MAGN_DEV_NAME },
 	{},
 };
 MODULE_DEVICE_TABLE(spi, st_magn_id_table);