ppc/pnv: fix dumpdtb option
The '-machine dumpdtb' command line option stopped working on PowerPC/pnv systems after recent design change [1]. Fixing this by generating fdt blob in `pnv_init`. [1] https://lore.kernel.org/qemu-devel/20250206151214.2947842-1-peter.maydell@linaro.org/ Cc: Aditya Gupta <adityag@linux.ibm.com> Cc: Harsh Prateek Bora <harshpb@linux.ibm.com> Cc: Peter Maydell <peter.maydell@linaro.org> Cc: BALATON Zoltan <balaton@eik.bme.hu> Cc: qemu-stable@nongnu.org Fixes: 8fd2518ef2f8d34 ("hw: Centralize handling of -machine dumpdtb option") Signed-off-by: Shivang Upadhyay <shivangu@linux.ibm.com> Reviewed-by: Peter Maydell <peter.maydell@linaro.org> Reviewed-by: Aditya Gupta <adityag@linux.ibm.com> Link: https://lore.kernel.org/qemu-devel/20260311143549.118720-1-shivangu@linux.ibm.com Signed-off-by: Harsh Prateek Bora <harshpb@linux.ibm.com>