hwmon: (adt7470) Fix incorrect return code check

In adt7470_write_word_data(), which writes two bytes using
i2c_smbus_write_byte_data(), the return codes are incorrectly AND-ed
together when they should be OR-ed together.

The return code of i2c_smbus_write_byte_data() is zero for success.

The upshot is only the first byte was ever written to the hardware.
The 2nd byte was never written out.

I noticed that trying to set the fan speed limits was not working
correctly on my system.  Setting the fan speed limits is the only
code that uses adt7470_write_word_data().  After making the change
the limit settings work and the alarms work also.
Signed-off-by: Curt Brune <curt@cumulusnetworks.com>
Cc: stable@vger.kernel.org
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

drivers/hwmon/adt7470.c

@@ -215,7 +215,7 @@ static inline int adt7470_write_word_data(struct i2c_client *client, u8 reg,
 					  u16 value)
 {
 	return i2c_smbus_write_byte_data(client, reg, value & 0xFF)
-	       && i2c_smbus_write_byte_data(client, reg + 1, value >> 8);
+	       || i2c_smbus_write_byte_data(client, reg + 1, value >> 8);
 }
 
 static void adt7470_init_client(struct i2c_client *client)