Remove support for 10.4 Tiger from AsmPrinter

I stumbled on this while trying to tighten Alignment in MCStreamer (D138705).
From the [wikipedia page](https://en.wikipedia.org/wiki/Mac_OS_X_Tiger), last release of MacOSX Tiger was released 15 years ago and is not supported anymore by Apple.

Relevant commit : https://github.com/llvm/llvm-project/commit/9f06f911d197577b80d208a167980833b4fb9ad5#diff-17b326b45ef392288420bed274616afa7df81b27576c96723b3c25f5198dc398

Differential Revision: https://reviews.llvm.org/D138707