hw/arm: add static NVDIMMs in device tree

hw/arm: add static NVDIMMs in device tree

NVDIMM is used for fast rootfs with EROFS, for example by kata
containers. To allow booting with static NVDIMM memory, add them to the
device tree in arm virt machine.

This allows users to boot directly with nvdimm memory devices without
having to rely on ACPI and hotplug.

Verified to work with command invocation:

./qemu-system-aarch64 \
  -M virt,nvdimm=on \
  -cpu cortex-a57 \
  -m 4G,slots=2,maxmem=8G \
  -object memory-backend-file,id=mem1,share=on,mem-path=/tmp/nvdimm,size=4G,readonly=off \
  -device nvdimm,id=nvdimm1,memdev=mem1,unarmed=off \
  -drive file=./debian-12-nocloud-arm64-commited.qcow2,format=qcow2 \
  -kernel ./vmlinuz-6.1.0-13-arm64 \
  -append "root=/dev/vda1 console=ttyAMA0,115200 acpi=off"
  -initrd ./initrd.img-6.1.0-13-arm64 \
  -nographic \
  -serial mon:stdio

Signed-off-by: Manos Pitsidianakis <manos.pitsidianakis@linaro.org>
Message-id: 20250807-nvdimm_arm64_virt-v2-1-b8054578bea8@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>