thunderbolt: Update deprecated firmware update site in icm.c

Update leftover reference to Thunderbolt firmware upgrade site
(thunderbolttechnology.net) with the preferred method described in
Documentation/admin-guide/thunderbolt.rst.

Signed-off-by: Alan Borzeszkowski <alan.borzeszkowski@linux.intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>

Author: aborzesz

drivers/thunderbolt/icm.c

@@ -2000,7 +2000,7 @@ static int icm_driver_ready(struct tb *tb)
 	if (icm->safe_mode) {
 		tb_info(tb, "Thunderbolt host controller is in safe mode.\n");
 		tb_info(tb, "You need to update NVM firmware of the controller before it can be used.\n");
-		tb_info(tb, "For latest updates check https://thunderbolttechnology.net/updates.\n");
+		tb_info(tb, "Use fwupd tool to apply update. Check Documentation/admin-guide/thunderbolt.rst for details.\n");
 		return 0;
 	}