ath10k: fix control-message timeout

USB control-message timeouts are specified in milliseconds and should
specifically not vary with CONFIG_HZ.

Fixes: 4db66499 ("ath10k: add initial USB support")
Cc: stable@vger.kernel.org      # 4.14
Cc: Erik Stromdahl <erik.stromdahl@gmail.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Link: https://lore.kernel.org/r/20211025120522.6045-2-johan@kernel.org

drivers/net/wireless/ath/ath10k/usb.c

@@ -525,7 +525,7 @@ static int ath10k_usb_submit_ctrl_in(struct ath10k *ar,
 			      req,
 			      USB_DIR_IN | USB_TYPE_VENDOR |
 			      USB_RECIP_DEVICE, value, index, buf,
-			      size, 2 * HZ);
+			      size, 2000);
 
 	if (ret < 0) {
 		ath10k_warn(ar, "Failed to read usb control message: %d\n",