Currently the default values of retry_interval and retry_timeout are set
to -1, when 'driver' option exists without retry fileds. It conflicts
with the default values when the 'driver' option does not exist.
So let's set default values of retry_interval and retry_timeout to 0 when
retry policy is not enabled.
Signed-off-by: Jiahui Cen <cenjiahui@huawei.com>
