mt7601u: use DEFINE_DEBUGFS_ATTRIBUTE to define debugfs fops

It is more clear to use DEFINE_DEBUGFS_ATTRIBUTE to define debugfs file
operation rather than DEFINE_SIMPLE_ATTRIBUTE.

Signed-off-by: zhong jiang <zhongjiang@huawei.com>
Acked-by: Jakub Kicinski <kubakici@wp.pl>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
diff --git a/drivers/net/wireless/mediatek/mt7601u/debugfs.c b/drivers/net/wireless/mediatek/mt7601u/debugfs.c
index 5e54983..300242b 100644
--- a/drivers/net/wireless/mediatek/mt7601u/debugfs.c
+++ b/drivers/net/wireless/mediatek/mt7601u/debugfs.c
@@ -27,7 +27,7 @@ mt76_reg_get(void *data, u64 *val)
 	return 0;
 }
 
-DEFINE_SIMPLE_ATTRIBUTE(fops_regval, mt76_reg_get, mt76_reg_set, "0x%08llx\n");
+DEFINE_DEBUGFS_ATTRIBUTE(fops_regval, mt76_reg_get, mt76_reg_set, "0x%08llx\n");
 
 static int
 mt7601u_ampdu_stat_read(struct seq_file *file, void *data)