Before the change described in
https://gcc.gnu.org/pipermail/gcc-patches/2023-September/631393.html it
appeared that inlining built-in GCC function __atomic_test_and_set() was
incorrect. It resulted in a non-atomic write.
For GCC toolchains which do not have such patch yet, this commit fixes
__atomic_test_and_set to be atomic in IDF's builds.
This updates the minimal supported version of CMake to 3.16, which in turn enables us to use more CMake features and have a cleaner build system.
This is the version that provides most new features and also the one we use in our latest docker image for CI.
Alexey Lapshin
Fu Hanxi
simon.chupin
Djordje Nedic
Ivan Grokhotkov
Marius Vikhammer