[clang] [flang] [clang][Driver] Add RPATH by default (PR #115286)

[Fangrui Song via cfe-commits]

MaskRay wrote:

Note: Some build systems want to handle DT_RUNPATH themselves (e.g. CMAKE_INSTALL_RPATH). Some distributions (e.g. Fedora) have policies against DT_RUNPATH for system packages.

While I can understand why some folks want to make -frtlib-add-rpath the default, I am not sure this is the majority of opinions.

https://github.com/llvm/llvm-project/pull/115286