thunderbolt: Check for NVM authentication status after the operation started

If the NVM authentication fails immediately, like if the firmware
detects that the image is not valid for some reason, better to read the
status once and if set to non-zero fail the operation accordingly.

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