[llvm] Remove iOS 5 check for tailcalls on ARM (PR #133354)

[via llvm-commits]

Un1q32 wrote:

> As far as I understand it was likely disabled for older ios versions due to an issue in the linker, which likely isn't present any more?

If that's the case, I might try to find what linker versions have this issue, and then check the linker version to disable tail calls.

https://github.com/llvm/llvm-project/pull/133354