netdevsim: Change dummy reporter auto recover default

Health reporters should be registered with auto recover set to true.
Align dummy reporter behaviour with that, as in later patch the option to
set auto recover behaviour will be removed.

In addition, align netdevsim selftest to the new default value.

Signed-off-by: Eran Ben Elisha <eranbe@mellanox.com>
Reviewed-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>