hwmon: (nct6775) use permission-specific DEVICE_ATTR variants

Use DEVICE_ATTR_RW for read/write attributes. This simplifies the source
code, improves readbility, and reduces the chance of inconsistencies.

The conversion was done automatically using coccinelle. It was validated
by compiling both the old and the new source code and comparing its text,
data, and bss size.

Signed-off-by: Julia Lawall <[e-mail]>
[groeck: Updated description]
Signed-off-by: Guenter Roeck <[e-mail]>

drivers/hwmon/nct6775.c

···
 };
 
 static ssize_t
-show_vid(struct device *dev, struct device_attribute *attr, char *buf)
+cpu0_vid_show(struct device *dev, struct device_attribute *attr, char *buf)
 {
 	struct nct6775_data *data = dev_get_drvdata(dev);
 
 	return sprintf(buf, "%d\n", vid_from_reg(data->vid, data->vrm));
 }
 
-static DEVICE_ATTR(cpu0_vid, S_IRUGO, show_vid, NULL);
+static DEVICE_ATTR_RO(cpu0_vid);
 
 /* Case open detection */