iio: imu: st_lsm6dsx: fix FIFO threshold mask for LSM6DSM/LSM6DSL

According to the latest datasheet, LSM6DSM and LSM6DSL imu sensors
export GENMASK(10, 0) for FIFO threshold mask definition. Despite
that is not an actual issue since write on fifo_th register is protected
by max_fifo_size value, fix fifo_th and fifo_diff register definitions

Fixes: 290a6ce1 ("iio: imu: add support to lsm6dsx driver")
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@redhat.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c

@@ -266,11 +266,11 @@ static const struct st_lsm6dsx_settings st_lsm6dsx_sensor_settings[] = {
 		.fifo_ops = {
 			.fifo_th = {
 				.addr = 0x06,
-				.mask = GENMASK(11, 0),
+				.mask = GENMASK(10, 0),
 			},
 			.fifo_diff = {
 				.addr = 0x3a,
-				.mask = GENMASK(11, 0),
+				.mask = GENMASK(10, 0),
 			},
 			.th_wl = 3, /* 1LSB = 2B */
 		},