iio: adis16480: fix devices that do not support sleep mode

Not all devices supported by this driver support being put to sleep
mode. For those devices, when calling 'adis16480_stop_device()' on the
unbind path, we where actually writing in the SYNC_SCALE register.

Fixes: 80cbc848c4fa0 ("iio: imu: adis16480: Add support for ADIS16490")
Fixes: 82e7a1b250170 ("iio: imu: adis16480: Add support for ADIS1649x family of devices")
Signed-off-by: Nuno Sá <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Cc: <[e-mail]>
Signed-off-by: Jonathan Cameron <[e-mail]>

drivers/iio/imu/adis16480.c

···
 	unsigned int max_dec_rate;
 	const unsigned int *filter_freqs;
 	bool has_pps_clk_mode;
+	bool has_sleep_cnt;
 	const struct adis_data adis_data;
 };
 
···
 		.temp_scale = 5650, /* 5.65 milli degree Celsius */
 		.int_clk = 2460000,
 		.max_dec_rate = 2048,
+		.has_sleep_cnt = true,
 		.filter_freqs = adis16480_def_filter_freqs,
 		.adis_data = ADIS16480_DATA(16375, &adis16485_timeouts, 0),
 	},
···
 		.temp_scale = 5650, /* 5.65 milli degree Celsius */
 		.int_clk = 2460000,
 		.max_dec_rate = 2048,
+		.has_sleep_cnt = true,
 		.filter_freqs = adis16480_def_filter_freqs,
 		.adis_data = ADIS16480_DATA(16480, &adis16480_timeouts, 0),
 	},
···
 		.temp_scale = 5650, /* 5.65 milli degree Celsius */
 		.int_clk = 2460000,
 		.max_dec_rate = 2048,
+		.has_sleep_cnt = true,
 		.filter_freqs = adis16480_def_filter_freqs,
 		.adis_data = ADIS16480_DATA(16485, &adis16485_timeouts, 0),
 	},
···
 		.temp_scale = 5650, /* 5.65 milli degree Celsius */
 		.int_clk = 2460000,
 		.max_dec_rate = 2048,
+		.has_sleep_cnt = true,
 		.filter_freqs = adis16480_def_filter_freqs,
 		.adis_data = ADIS16480_DATA(16488, &adis16485_timeouts, 0),
 	},
···
 	if (ret)
 		return ret;
 
-	ret = devm_add_action_or_reset(&spi->dev, adis16480_stop, indio_dev);
-	if (ret)
-		return ret;
+	if (st->chip_info->has_sleep_cnt) {
+		ret = devm_add_action_or_reset(&spi->dev, adis16480_stop,
+					       indio_dev);
+		if (ret)
+			return ret;
+	}
 
 	ret = adis16480_config_irq_pin(spi->dev.of_node, st);
 	if (ret)