Fix parsing of big float literals (#29940)
Summary:
Stacked PRs
* **#29940 - [jit] Fix parsing of big float literals**
* #29935 - [jit] Fix hex literal parsing
* #29931 - [jit] Throw a better error for int too big for int64_t
](https://our.intern.facebook.com/intern/diff/19186604/)
Pull Request resolved: https://github.com/pytorch/pytorch/pull/29940
Pulled By: driazati
Differential Revision: D19186604
fbshipit-source-id: 6ef66588a5cf956f281e7bd1e5584ef06f5296e9
