Add BSP for STM32H7

[Sebastian Huber]

On 19/03/2020 09:32, Sebastian Huber wrote:

> Hello,
>
> I started to work on a BSP for the STM32H7:
>
> https://devel.rtems.org/ticket/3910
>
> I will use the new build system for this BSP.

I finished the BSP for the STM32H7. It includes clock, console, random 
number, Ethernet (libbsd), and USB host drivers. It uses the new build 
system. If someone is interested, I can push it to the new build system 
branch:

https://git.rtems.org/sebh/rtems.git/log/?h=build