Use ark_ff::batch_inversion for point normalization

[Pratyush]

Description

Reuses existing batch inversion code for batch normalization. Enables better parallelization, at the expense of some more allocation.

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[ValarDragon]

LGTM, glad we'll get parallel batch inversion speedups here!

I wonder if we should eventually restructure this to use split the vector into chunks, and operate on each chunk in parallel. (Using a serial batch inversion on that chunk)
That would keep the data being mutated in the final loop thread-local

[Pratyush]

I think that's possible if we don't unify the logic with batch_inversion (essentially if we duplicate the logic in batch_inversion)

[ValarDragon]

Yeah I think we would have to duplicate that. We probably should move that standard chunk setup code to an ark-std macro