add release/v4.0 sntp logic to release/v3.3 (IDFGH-1902)

[erki1993]

Hello!

esp-idf version release/v4.0 has additional SNTP logic that could also be ported to release/v3.3.

The functionality we would like to get on v3.3 is sntp_set_time_sync_notification_cb as otherwise there is no way to detect when system time is updated.

Regards,
Erki

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[KonstantinKondrashov]

Hi erki1993!
Thank you for your interest in this. I'll do backport on 3.3. Thank you.

[KonstantinKondrashov]

Hi @erki1993!
I have created an MR into our internal repository it will be merged ASAP. Thanks.

[erki1993]

Hi @KonstantinKondrashov any news on the merge?

[Alvin1Zhang]

@erki1993 Thanks for contribution, please refer to 07a3eca. Thanks.