[Bug target/85397] -mcet -fcf-protection doesn't work with label in nested function

[hjl.tools at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85397

--- Comment #2 from H.J. Lu <hjl.tools at gmail dot com> ---
Please take a look at hjl/cet/master branch at

https://github.com/hjl-tools/gcc/tree/hjl/cet/master

I replaced builtin_setjmp_setup and builtin_longjmp with save_stack_nonlocal
and restore_stack_nonlocal to save and restore shadow stack to support both
builtin setjmp/longjmp as well as non-local goto in nested functions.