hwmon: (it87) Improve temperature reporting support

Add test if thermistor sensor type attribute should be visible, i.e.
test if the attribute is defined.

Signed-off-by: Frank Crawford <frank@crawford.emu.id.au>
Link: https://lore.kernel.org/r/20230707123005.956415-3-frank@crawford.emu.id.au
[groeck: Dropped unnecessary 'type' variable in it87_temp_is_visible()]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

drivers/hwmon/it87.c

@@ -2328,6 +2328,12 @@ static umode_t it87_temp_is_visible(struct kobject *kobj,
 	if (!(data->has_temp & BIT(i)))
 		return 0;
 
+	if (a == 3) {
+		if (get_temp_type(data, i) == 0)
+			return 0;
+		return attr->mode;
+	}
+
 	if (a == 5 && !has_temp_offset(data))
 		return 0;