[inductor] Use divisor_override param in in aten.divisor_override lowering (#107401)
Summary: Just mirrored the treatment of this param from here: https://codebrowser.bddppq.com/pytorch/pytorch/aten/src/ATen/native/cuda/AveragePool2d.cu.html#171
Test Plan:
`python test/inductor/test_torchinductor_opinfo.py -k test_comprehensive_nn_functional_avg_pool2d`
Pull Request resolved: https://github.com/pytorch/pytorch/pull/107401
Approved by: https://github.com/eellison
