Fix bug in ingroup_inds

Author: chenshi3

pcdet/ops/ingroup_inds/src/ingroup_inds_kernel.cu

@@ -3,10 +3,8 @@
 #include <math.h>
 #include <stdio.h>
 #include <torch/serialize/tensor.h>
-#include <torch/extension.h>
 #include <torch/types.h>
 #include "cuda_fp16.h"
-// #include "error.cuh"
 
 #define CHECK_CALL(call)                                   \
 do                                                    \