arch_prctl.2, execveat.2, fanotify_mark.2, fcntl.2, fork.2, madvise.2, mknod.2, mmap...

arch_prctl.2, execveat.2, fanotify_mark.2, fcntl.2, fork.2, madvise.2, mknod.2, mmap.2, modify_ldt.2, mount.2, open.2, prctl.2, ptrace.2, restart_syscall.2, seccomp.2, semop.2, set_thread_area.2, symlink.2, umount.2, unlink.2, error.3, getnetent.3, getprotoent.3, getservent.3, getutent.3, glob.3, login.3, setjmp.3, setnetgrent.3, wordexp.3, epoll.7: Remove section number from page self reference

Fix places where pages refer to the function that they describe
and include a section number in that reference. Such references
cause some HTML-rendering tools to create self-references in the
page.

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>