Glibc 2.32 porting notes/sysctl.h removal
From Gentoo Wiki
From upstream release notes:
* The deprecated <sys/sysctl.h> header and the sysctl function have been removed. To support old binaries, the sysctl function continues to exist as a compatibility symbol (on those architectures which had it), but always fails with ENOSYS. This reflects the removal of the system call from all architectures, starting with Linux 5.5.