[llvm] RuntimeLibcalls: Add entries for __security_check_cookie (PR #151843)

[Paul Walker via llvm-commits]

paulwalker-arm wrote:

I'm not familiar with `__security_check_cookie` so I'll apologise now if these are silly questions.

The PR looks good from the point of view of removing the hardcode function names but does struct the logic differently.  The original code is typically of the form:
```
if isWindowsMSVCEnvironment
  // do something windows specific where security_check_cookie is known to exists
```
into
```
if security_check_cookie exist
  // do something security_check_cookie specific
```
Is this expected? Is the presents of security_check_cookie enough to imply isWindowsMSVCEnvironment (not withstanding the current definition of SecurityCheckCookieIfWinMSVC).

Would is make sense to keep the `if isWindowsMSVCEnvironment` structure but then require/assert the RTLIB::LibcallImpl is supported?

https://github.com/llvm/llvm-project/pull/151843