main/postmarketos-mkinitfs: Use the original filename for the dtb
Looking at the contents of the rootfs chroot, it should be fine but it should still be tested on at least one device.
@craftyguy Not really related here, but for the Librem 5, imx8mq-librem5-devkit.dtb should be used, as indicated by https://source.puri.sm/Librem5/linux-next/commit/b26766d2adad0423efd88dc28f194db7de624bb9 (and a few other issues in the repo)
Edited by Luca Weiss