There is no need to abort attribute setting or object addition, if the
prepare phase returned operation not supported.

Thus, abort these two transactions only if the error is not -EOPNOTSUPP.

Signed-off-by: Vivien Didelot <vivien.didelot@savoirfairelinux.com>
Acked-by: Jiri Pirko <jiri@resnulli.us>
Acked-by: Scott Feldman <sfeldma@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>