[llvm] [X86] Don't emit ENDBR for asm goto branch targets (PR #143439)

[Peter Smith via llvm-commits]

smithp35 wrote:

This looks fine to me, and reflects existing x86 GCC behaviour. I've added some x86 backend maintainers. As an Arm employee I'd best not appove an exclusively x86 change. 

https://github.com/llvm/llvm-project/pull/143439