[Feature] - Add Support for creating DIFile with checksum information and source text.

[smaillet]

Is your feature request related to a problem? Please describe. Can't create a DIFile with any Checksum Information or source text

Describe the solution you'd like Add optional parameters (default to "none" semantics) to DiBuilder.CreateFile to allow adding the checksum information. This will include creating a new value type for the checksum info, and enum for checksum kind, as well as new LibLLVM* APIs to create the DIFile as the existing LLVM-C API does not provide support for these parameters.

Describe alternatives you've considered Wait around for the official LLVM-C API to catch up to changes in the underlying LLVM... [Not something that's worked well over time.]