s390/qeth: don't special-case HW trap during suspend

It makes no difference whether we
1. manually disarm the HW trap and call the offline code with
   recovery_mode == 1, or
2. call the offline code with recovery_mode == 0, and let it disarm the
   HW trap for us.

So consolidate the two code paths in the suspend callback.

Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>