Instead of using argc directly, all CSA builtins should use
CodeStubArguments::GetLength().

Bug: v8:11112
Change-Id: Ib62d9d9240e8d42b6b7daed5bdf63f7ab0943fd9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2563879
Commit-Queue: Patrick Thier <pthier@chromium.org>
Reviewed-by: Victor Gomes <victorgomes@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Cr-Commit-Position: refs/heads/master@{#71504}