[clang] [Driver] Corrections for linker flags passed with relocatable linking on OpenBSD (PR #67254)

[Fangrui Song via cfe-commits]

MaskRay wrote:

`-Bdynamic` is the linker default, so you can remove it. Gnu.cpp uses `-Bdynamic` like `)` to close `-Bstatic`: `-Bstatic ... `-Bdynamic`

https://github.com/llvm/llvm-project/pull/67254