Commit 6337d53fdf breaks PDU001 board

[Felix Brack]

Hello,

Git bisect reports commit 6337d53fdf (sync am33xx with Linux 5.9-rc7) to
break the PDU001 board. I have tried to figure out what the problem is
but failed.
It looks like the SPL is not loading any drivers, not even the pin
controller driver. Enabling an early debug UART did not help as it only
reports the debug UART startup message.
For me this looks like a very basic device tree problem but I just can't
figure out how to get things working again. Any hint would be very much
appreciated.

Regards, Felix