mt76: mt76u: extend RX scatter gather number

Set RX scatter gather number to 4 in order to extend the maximum AMSDU
size to 11,454.
Signed-off-by: NSean Wang <sean.wang@mediatek.com>
Co-developed-by: NLorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: NLorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: NFelix Fietkau <nbd@nbd.name>

drivers/net/wireless/mediatek/mt76/mt76.h

@@ -389,7 +389,7 @@ enum mt76u_out_ep {
 };
 
 #define MT_TX_SG_MAX_SIZE	8
-#define MT_RX_SG_MAX_SIZE	1
+#define MT_RX_SG_MAX_SIZE	4
 #define MT_NUM_TX_ENTRIES	256
 #define MT_NUM_RX_ENTRIES	128
 #define MCU_RESP_URB_SIZE	1024