tashaboot: devicetree relocate and grow, real chosen properties

Firmware edits the devicetree it hands the kernel: new
properties cannot go into a packed fdt in place, the blob moves
to scratch first and the blocks grow there. The insert moves the
strings block up by the prop size, opens the prop slot before
/chosen's end token, the new name lands at the strings end, and
all four header fields track the geometry, totalsize, off_dt_
strings, size_dt_strings and size_dt_struct. The last one bounds
the token walk in libfdt and a stale value there reads as
BADSTRUCTURE, the kernel parsed no memory node and panicked on
page table allocation before the first print.

The strings block length comes from the size_dt_strings header
field, not totalsize minus off_dt_strings, qemu's tree carries
a hole after the strings block and the subtraction drags it
along as tree.

The initrd start and end land in /chosen as real properties now,
the initrd= bootargs shortcut is gone.

receipt: smp brought up 1 node 4 cpus, run /init, userspace,
busybox shell, the initrd mounted from the chosen cells.

0 files changed, 0 insertions, 0 deletions