accept.2, acct.2, epoll_create.2, execve.2, futex.2, inotify_init.2, mmap.2, open...

accept.2, acct.2, epoll_create.2, execve.2, futex.2, inotify_init.2, mmap.2, open.2, pipe.2, shmget.2, socket.2, socketpair.2, spu_create.2, swapon.2, uselib.2, getgrent.3, getgrnam.3, getlogin.3, getpwent.3, getpwnam.3, mq_open.3, opendir.3, sem_open.3, shm_open.3, tmpfile.3, fanotify.7: ERRORS: standardize text for ENFILE error

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