[llvm] Add new llvm.dbg.declare_value intrinsic. (PR #168132)

[Shubham Sandeep Rastogi via llvm-commits]

rastogishubham wrote:

> I think this looks good — could you add a `llvm-as | llvm-dis | llvm-as | llvm-dis` roundtrip test to the IR Assembler test directory?

Done! I am not sure what to check for, so I just checked that there was a #dbg_declare_value still present. Please let me know if I should change something

https://github.com/llvm/llvm-project/pull/168132