Add machine db entries for solidrun am64 based hummingboard-t

Add machine db entries for the SolidRun AM6442 SoC based HummingBoard-T that has been supported in the kernel sinve v6.10 1.

It uses a vendor fork of U-Boot with support for distro-boot features.

Signed-off-by: Josua Mayer josua@solid-run.com