ath9k: Fix regression with Atheros 9271

This fix allows ath9k_htc modules to connect to WLAN once again.

Fixes: 2bbcaaee1f ("ath9k: Fix general protection fault in ath9k_hif_usb_rx_cb")
Link: https://bugzilla.kernel.org/show_bug.cgi?id=208251
Signed-off-by: Mark O'Donovan <shiftee@posteo.net>
Reported-by: Roman Mamedov <rm@romanrm.net>
Tested-by: Viktor Jägersküpper <viktor_jaegerskuepper@freenet.de>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20200711043324.8079-1-shiftee@posteo.net

drivers/net/wireless/ath/ath9k/hif_usb.c

@@ -733,11 +733,13 @@ static void ath9k_hif_usb_reg_in_cb(struct urb *urb)
 			return;
 		}
 
+		rx_buf->skb = nskb;
+
 		usb_fill_int_urb(urb, hif_dev->udev,
 				 usb_rcvintpipe(hif_dev->udev,
 						 USB_REG_IN_PIPE),
 				 nskb->data, MAX_REG_IN_BUF_SIZE,
-				 ath9k_hif_usb_reg_in_cb, nskb, 1);
+				 ath9k_hif_usb_reg_in_cb, rx_buf, 1);
 	}
 
 resubmit: