wcn36xx: Add a chip identifier for WCN3680

The WCN3680 has some specific behaviours that we want to capture to
distinguish it from the WCN3620 and WCN3660 respectively.

Add an identifier for this purpose.
Signed-off-by: Bryan O'Donoghue <bryan.odonoghue@linaro.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200829033846.2167619-2-bryan.odonoghue@linaro.org

drivers/net/wireless/ath/wcn36xx/wcn36xx.h

@@ -92,6 +92,7 @@ enum wcn36xx_ampdu_state {
 
 #define RF_UNKNOWN	0x0000
 #define RF_IRIS_WCN3620	0x3620
+#define RF_IRIS_WCN3680	0x3680
 
 static inline void buff_to_be(u32 *buf, size_t len)
 {