[Bug libstdc++/105540] [11 Regression] gcc-11-20220506 failure to build on Cygwin due to lack of secure_getenv

[redi at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105540

--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> ---
I forgot to backport r12-6867