[U-Boot] Modify DTB after loading fitimage

[Peter Fink]

Hi!

I have an usecase where I would like to have a single fitimage including 
DTBs for multiple devices. But I also have to modify two nodes inside 
the DTB before booting.

How would I modify the chosen DTB file with the fdt command after 
loading the fitimage?
Is it even possible to accomplish this goal?

It would also be ok if all DTBs inside the fitimage would be modified 
prior to booting, because boot time is not an issue here.

Thanks in advance & best regards,
Peter