getsockopt

Results 2 issues of getsockopt

related issue: https://github.com/openconfig/reference/issues/233

Hi all According to [gnmi-specification](https://github.com/openconfig/reference/blob/master/rpc/gnmi/gnmi-specification.md) a target should "sync all data to client" firstly no matter what current subscription mode(`ONCE` `POLL` `STREAM/SAMPLE` `STREAM/ON_CHANGE`) is. However the [netconf event](https://datatracker.ietf.org/doc/html/rfc5277)/yang `notification` may...