Buildroot commitaccb006d9bbumped libheif to version 1.20.1 which includes several commits unconditionally depen- ding on std::mutex which requires a toolchain with threads:14f956726c6bb8cdaa8aAdd dependency to BR2_TOOLCHAIN_HAS_THREADS to Config.in, remove configure options handling non-threaded toolchains and adjust a Config.in comment of the only dependee kodi-imagedecoder-heif. Fixes: https://autobuild.buildroot.net/results/28b/28bf68147382dada33cbf9b299396dfdee3fbbe6/ Signed-off-by: Bernd Kuhls <bernd@kuhls.net> Signed-off-by: Peter Korsgaard <peter@korsgaard.com> (cherry picked from commit02f5061eb0) Signed-off-by: Thomas Perale <thomas.perale@mind.be>