[quant] Add optimized approach to calculate qparams for qembedding_bag (#45149)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/45149
The choose_qparams_optimized calculates the the optimized qparams.
It uses a greedy approach to nudge the min and max and calculate the l2 norm
and tries to minimize the quant error by doing `torch.norm(x-fake_quant(x,s,z))`
Test Plan: Imported from OSS
Reviewed By: raghuramank100
Differential Revision: D23848060
fbshipit-source-id: c6c57c9bb07664c3f1c87dd7664543e09f634aee
