add support for STM32N6 

### Description

Seek to add support for STM32N6，Because it's coming out soon

### Code Size

Seek to add support for STM32N6，Because it's coming out soon

### Implementation

I hope the MicroPython maintainers or community will implement this feature, I intend to implement this feature and would submit a Pull Request if desirable

### Code of Conduct

Yes, I agree