kho_add_subtree
int kho_add_subtree(const char *name, void *fdt);
EXPORT_SYMBOL_GPL(kho_add_subtree);
err = kho_add_subtree(LUO_FDT_KHO_ENTRY_NAME, fdt_out);
err = kho_add_subtree(KHO_TEST_FDT, folio_address(state->fdt));
err = kho_add_subtree(MEMBLOCK_KHO_FDT, fdt);