maiko: fnctl with F_SETFL has no valid return value apart from -1

[waywardmonkeys]

The return value of fcntl when passed F_SETFL is only either -1 or something else.

We should look at each of these and probably remove the assignment:

../src/Cldeetr.c:      flags = fcntl(ether_fd, F_SETFL, flags | FASYNC | FNDELAY);
../src/chardev.c:  rval = fcntl(fd, F_SETFL, rval);
../src/ether.c:        flags = fcntl(ether_fd, F_SETFL, flags | O_NDELAY);
../src/ldeether.c:      flags = fcntl(ether_fd, F_SETFL, flags | O_NDELAY);
../src/ldeether.c:      flags = fcntl(ether_fd, F_SETFL, flags | FASYNC | FNDELAY);
../src/oldeether.c:      flags = fcntl(ether_fd, F_SETFL, flags | FASYNC | FNDELAY);
../src/osmsg.c:  flags = fcntl(cons_pty, F_SETFL, (flags | FASYNC | FNDELAY));
../src/socdvr.c:      res = fcntl(XServer_Fd, F_SETFL, res);
../src/unixcomm.c:    flags = fcntl(res, F_SETFL, flags);
../src/unixcomm.c:        res = fcntl(PipeFD, F_SETFL, res);
../src/unixcomm.c:        res = fcntl(Master, F_SETFL, res);
../src/unixcomm.c:      res = fcntl(sockFD, F_SETFL, res);
../src/unixfork.c:  res = fcntl(LispPipeIn, F_SETFL, res);