[Fix] Fix DynamicPillarFeaureNet incorrect index caused by modifications of PillarFeatureNet

[Xiangxu-0103]

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[Xiangxu-0103]

Sorry for deleting the fix_dv branch in my repo by mistake and re-pull this PR.

[Tai-Wang]

The performance does not change compared with that before the modifications of PillarFeatureNet while a little lower than that before coordinate system refactoring. Consider merging this PR first and then calibrating the performance by checking the dynamic voxelization.