[clang] [Clang][NFC] Remove '--' separator in the linker wrapper usage (PR #84253)

[Joseph Huber via cfe-commits]

jhuber6 wrote:

> > [NFC]
> 
> From a strict interpretation, this is not NFC as this changes clang driver behavior. The overall behavior combining clang + clang-linker-wrapper may not change, though...

I suppose I just wanted to make it clear that this option didn't do anything, but it does technically change stuff. Thanks for the review.

https://github.com/llvm/llvm-project/pull/84253