[JIT] Frozen Graph Linear-BatchNormNd Folding (#86706)
This PR adds linear-batchnormNd folding for JIT frozen graphs.
**Performance benchmark**
A preliminary benchmark with a simple model of linear+bn1d tested on first socket, physical cores of skylake machine.
**FP32, JIT**
without linear-bn folding
with linear-bn folding
Pull Request resolved: https://github.com/pytorch/pytorch/pull/86706
Approved by: https://github.com/davidberard98
