iio: chemical: bme680: use GENMASK macro

Replace hardcoded bit masks with GENMASK macro
Signed-off-by: David Frey <dpfrey@gmail.com>
Reviewed-by: Himanshu Jha <himanshujha199640@gmail.com>
Tested-by: Himanshu Jha <himanshujha199640@gmail.com>
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/chemical/bme680.h

@@ -18,7 +18,7 @@
 #define BME680_REG_GAS_MSB			0x2A
 #define BME680_REG_GAS_R_LSB			0x2B
 #define   BME680_GAS_STAB_BIT			BIT(4)
-#define   BME680_GAS_RANGE_MASK			0x0F
+#define   BME680_GAS_RANGE_MASK			GENMASK(3, 0)
 
 #define BME680_REG_CTRL_HUMIDITY		0x72
 #define   BME680_OSRS_HUMIDITY_MASK		GENMASK(2, 0)
@@ -39,13 +39,13 @@
 
 #define BME680_MAX_OVERFLOW_VAL			0x40000000
 #define BME680_HUM_REG_SHIFT_VAL		4
-#define BME680_BIT_H1_DATA_MASK			0x0F
+#define BME680_BIT_H1_DATA_MASK			GENMASK(3, 0)
 
 #define BME680_REG_RES_HEAT_RANGE		0x02
-#define   BME680_RHRANGE_MASK			0x30
+#define   BME680_RHRANGE_MASK			GENMASK(5, 4)
 #define BME680_REG_RES_HEAT_VAL			0x00
 #define BME680_REG_RANGE_SW_ERR			0x04
-#define   BME680_RSERROR_MASK			0xF0
+#define   BME680_RSERROR_MASK			GENMASK(7, 4)
 #define BME680_REG_RES_HEAT_0			0x5A
 #define BME680_REG_GAS_WAIT_0			0x64
 #define BME680_ADC_GAS_RES_SHIFT		6