void dump_verilog_pb_primitive_lut(FILE* fp,
char* subckt_prefix,
t_pb* prim_pb,
t_logical_block* mapped_logical_block,
t_pb_graph_node* cur_pb_graph_node,
int index,
t_spice_model* spice_model,
int lut_status,
t_rr_node* pb_rr_graph);