rt2800: set max_psdu to 3 on usb devices

All Ralink USB devices I have, including old ones, work well with
max_psdu = 3 (64kB tx AMPDUs).

Fix indent on the way.
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>

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

@@ -4743,15 +4743,16 @@ static int rt2800_init_registers(struct rt2x00_dev *rt2x00dev)
 
 	rt2800_register_read(rt2x00dev, MAX_LEN_CFG, &reg);
 	rt2x00_set_field32(&reg, MAX_LEN_CFG_MAX_MPDU, AGGREGATION_SIZE);
-	if (rt2x00_rt_rev_gte(rt2x00dev, RT2872, REV_RT2872E) ||
-	    rt2x00_rt(rt2x00dev, RT2883) ||
-	    rt2x00_rt_rev_lt(rt2x00dev, RT3070, REV_RT3070E)) {
+	if (rt2x00_is_usb(rt2x00dev)) {
+		drv_data->max_psdu = 3;
+	} else if (rt2x00_rt_rev_gte(rt2x00dev, RT2872, REV_RT2872E) ||
+		   rt2x00_rt(rt2x00dev, RT2883) ||
+		   rt2x00_rt_rev_lt(rt2x00dev, RT3070, REV_RT3070E)) {
 		drv_data->max_psdu = 2;
-		rt2x00_set_field32(&reg, MAX_LEN_CFG_MAX_PSDU, 2);
 	} else {
 		drv_data->max_psdu = 1;
-		rt2x00_set_field32(&reg, MAX_LEN_CFG_MAX_PSDU, 1);
 	}
+	rt2x00_set_field32(&reg, MAX_LEN_CFG_MAX_PSDU, drv_data->max_psdu);
 	rt2x00_set_field32(&reg, MAX_LEN_CFG_MIN_PSDU, 10);
 	rt2x00_set_field32(&reg, MAX_LEN_CFG_MIN_MPDU, 10);
 	rt2800_register_write(rt2x00dev, MAX_LEN_CFG, reg);