STM32MP257: support of ubuntu 20.0.4

[annguyen96vn]

Hello ! 
I am developing a STM32mp257FAI3 board.
Does STM32mp257FAI3 support ubuntu 20.0.4 operating system?

[anpa]

But why it would not support? Check the minimum requirements from canonical and keep that in mind during board development. Kernel also needs to be from canonical or just the packages?