[Export, AOTInductor] Populate ShapeEnv's var_to_val during deserialization (#121759)
Summary:
Deserialization didn't populate ShapeEnv's `var_to_val` field properly, and AOTInductor is relying on this field to compile dynamic shape properly.
As a result, when AOTI failed at compiling a deserialized ExportedProgram.
Test Plan: buck2 test mode/dev-nosan caffe2/test/inductor/fb:test_aot_inductor_pt2_inference
Differential Revision: D54559494
Pull Request resolved: https://github.com/pytorch/pytorch/pull/121759
Approved by: https://github.com/avikchaudhuri
