[llvm] [IR] Fix a few implicit conversions from TypeSize to uint64_t. NFC (PR #159894)

[Craig Topper via llvm-commits]

topperc wrote:

> Is the plan here to also eventually get rid of the implicit conversion similar to the plan for conversions from `Register`/`MCRegister` and `unsigned`?

Yes see. https://github.com/llvm/llvm-project/issues/159290

https://github.com/llvm/llvm-project/pull/159894