wil6210: wmi: Remove useless code

Fix the following whitescan warning:

An unsigned value can never be less than 0.
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Chong <jiapeng.chong@linux.alibaba.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/1617788766-91433-1-git-send-email-jiapeng.chong@linux.alibaba.com

drivers/net/wireless/ath/wil6210/wmi.c

@@ -1456,7 +1456,7 @@ static void wil_link_stats_store_basic(struct wil6210_vif *vif,
 	u8 cid = basic->cid;
 	struct wil_sta_info *sta;
 
-	if (cid < 0 || cid >= wil->max_assoc_sta) {
+	if (cid >= wil->max_assoc_sta) {
 		wil_err(wil, "invalid cid %d\n", cid);
 		return;
 	}