ovn-nbctl: Daemon mode should retry when IDL connection lost.

ovn-nbctl: Daemon mode should retry when IDL connection lost.

When creating IDL, "retry" was set to false. However, in daemon
mode, reconnecting upon DB server failure should be transparent
to user. This even impacts HA mode. E.g. in clustered mode, although
IDL tries to connect to next server, but at the first retry the
server fail-over may not be completed yet, and it stops retry after
N (N = number of remotes) times.

This patch makes sure in daemon mode retry is set to true so that
the daemon will automatically retry forever.

Signed-off-by: Han Zhou <hzhou8@ebay.com>
Signed-off-by: Ben Pfaff <blp@ovn.org>