Develop HAL RTC interaction and callback layer for PTP

Description

Right now we use the UDP userspace PTP from ThreadX NetX.
See https://github.com/eclipse-threadx/rtos-docs/blob/main/rtos-docs/netx-duo/netx-duo-ptp-client/chapter1.md.

We use the soft client timer callback. Thats bad.

Acceptance Criteria

Uses STM32 H5 RTC object in order to implement the hard clock callback. Support sub microsecond precision.

Proposed Solution

Edit the PTP client in our ethernet file (do not edit copied NetX source) to use the callback of the RTC. Whether the callback should be in Embedded base or the parent is up to you. Just note if you do it here:

• You must somehow take in a RTC. Can be H5 specific for now.
• You must ensure the RTC timer tick is accurate.

Make sure to read about the finer points of sub second accuracy in the STM docs and forums.