[llvm] [LLVM][CMake][MSVC] Install PDBs alongside executables (PR #120683)

[Saleem Abdulrasool via llvm-commits]

https://github.com/compnerd commented:

I think that you should use `LLVM_ENABLE_PDB` instead of `MSVC` for the condition. However, I agree with @aganea that size is a concern. OTOH, this is primarily either used for staging and then subsequently building the installer (which could/would drop the PDB, so the distribution size shouldn't be impacted, in theory) or it is for the developer installing it to the system for some reason.

I think that @zmodem should verify that the installer would not package up the PDBs.

https://github.com/llvm/llvm-project/pull/120683