mtd: rawnand: r852: use DEVICE_ATTR_RO() helper macro

Use DEVICE_ATTR_RO() helper macro instead of plain DEVICE_ATTR(), which
makes the code a bit shorter and easier to read.

Signed-off-by: Zhen Lei <[e-mail]>
Signed-off-by: Miquel Raynal <[e-mail]>
Link: https://lore.kernel.org/linux-mtd/[e-mail]

drivers/mtd/nand/raw/r852.c

···
 	r852_write_reg(dev, R852_CARD_IRQ_ENABLE, card_detect_reg);
 }
 
-static ssize_t r852_media_type_show(struct device *sys_dev,
-			struct device_attribute *attr, char *buf)
+static ssize_t media_type_show(struct device *sys_dev,
+			       struct device_attribute *attr, char *buf)
 {
 	struct mtd_info *mtd = container_of(sys_dev, struct mtd_info, dev);
 	struct r852_device *dev = r852_get_dev(mtd);
···
 	strcpy(buf, data);
 	return strlen(data);
 }
-
-static DEVICE_ATTR(media_type, S_IRUGO, r852_media_type_show, NULL);
+static DEVICE_ATTR_RO(media_type);
 
 
 /* Detect properties of card in slot */