mt76: mt7921: always wake device if necessary in debugfs

Add missing device wakeup in debugfs code if we are accessing chip
registers.

Fixes: 1d8efc7 ("mt76: mt7921: introduce Runtime PM support")
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Felix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt7921/debugfs.c

@@ -95,6 +95,8 @@ mt7921_tx_stats_show(struct seq_file *file, void *data)
 	struct mt7921_dev *dev = file->private;
 	int stat[8], i, n;
 
+	mt7921_mutex_acquire(dev);
+
 	mt7921_ampdu_stat_read_phy(&dev->phy, file);
 
 	/* Tx amsdu info */
@@ -104,6 +106,8 @@ mt7921_tx_stats_show(struct seq_file *file, void *data)
 		n += stat[i];
 	}
 
+	mt7921_mutex_release(dev);
+
 	for (i = 0; i < ARRAY_SIZE(stat); i++) {
 		seq_printf(file, "AMSDU pack count of %d MSDU in TXD: 0x%x ",
 			   i + 1, stat[i]);
@@ -124,6 +128,8 @@ mt7921_queues_acq(struct seq_file *s, void *data)
 	struct mt7921_dev *dev = dev_get_drvdata(s->private);
 	int i;
 
+	mt7921_mutex_acquire(dev);
+
 	for (i = 0; i < 16; i++) {
 		int j, acs = i / 4, index = i % 4;
 		u32 ctrl, val, qlen = 0;
@@ -143,6 +149,8 @@ mt7921_queues_acq(struct seq_file *s, void *data)
 		seq_printf(s, "AC%d%d: queued=%d\n", acs, index, qlen);
 	}
 
+	mt7921_mutex_release(dev);
+
 	return 0;
 }