thunderbolt: Check for Intel vendor ID when identifying controller

commit 35ee69e9 upstream.

With USB4 there will be other vendors so make sure the current checks
for different Intel controllers will not accidentally match those.

Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Liwei Song <liwei.song@windriver.com>