wifi: rt2x00: fix HT20/HT40 bandwidth switch on MT7620

Add missing configuration of the channel bandwidth filter to the
channel setup function for MT7620.
Reported-by: Serge Vasilugin <vasilugin@yandex.ru>
Signed-off-by: Daniel Golle <daniel@makrotopia.org>
Acked-by: Stanislaw Gruszka <stf_xl@wp.pl>
Signed-off-by: Kalle Valo <kvalo@kernel.org>
Link: https://lore.kernel.org/r/1664d89ba149f7b0bcec18b2a2abaedf49654507.1663445157.git.daniel@makrotopia.org

drivers/net/wireless/ralink/rt2x00/rt2800lib.c

@@ -3855,6 +3855,14 @@ static void rt2800_config_channel_rf7620(struct rt2x00_dev *rt2x00dev,
 		rfcsr |= tx_agc_fc;
 		rt2800_rfcsr_write_bank(rt2x00dev, 7, 59, rfcsr);
 	}
+
+	if (conf_is_ht40(conf)) {
+		rt2800_bbp_glrt_write(rt2x00dev, 141, 0x10);
+		rt2800_bbp_glrt_write(rt2x00dev, 157, 0x2f);
+	} else {
+		rt2800_bbp_glrt_write(rt2x00dev, 141, 0x1a);
+		rt2800_bbp_glrt_write(rt2x00dev, 157, 0x40);
+	}
 }
 
 static void rt2800_config_alc(struct rt2x00_dev *rt2x00dev,