[compiler-rt] compiler-rt: sanitizer_common: use close_range() instead of looping (PR #114442)

[Kyle Evans via llvm-commits]

kevans91 wrote:

> The `close_range` was added in FreeBSD 12.2. This is not a concern for building LLVM? I'm adding support for Linux in #191450.

I can't speak for Linux, but FreeBSD has notably tighter and well-defined support cycles that make it a little easier to do things like this- by the time this PR was opened, 12.2 was EOL for two years.

https://github.com/llvm/llvm-project/pull/114442