remove SIGABRT from sigwait list

[vtjnash]

This already is added to the sigdie list, so on mach it was attempting to handle it in both places simultaneously.

[inkydragon]

This already is added to the sigdie

xref:

julia/src/signals-unix.c

Line 1040 in 186634e

act_die.sa_sigaction = sigdie_handler;

julia/src/signals-unix.c

Lines 1045 to 1047 in 186634e

	if (sigaction(SIGABRT, &act_die, NULL) < 0) {
	jl_errorf("fatal error: sigaction: %s", strerror(errno));
	}

---

It looks like SIGINFO and SIGUSR1 have the same problem.

sigwait:

julia/src/signals-unix.c

Lines 647 to 653 in 186634e

	const static int sigwait_sigs[] = {
	SIGINT, SIGTERM, SIGABRT, SIGQUIT,
	#ifdef SIGINFO
	SIGINFO,
	#else
	SIGUSR1,
	#endif

sigdie:

julia/src/signals-unix.c

Lines 1053 to 1061 in 186634e

	#ifdef SIGINFO
	if (sigaction(SIGINFO, &act_die, NULL) < 0) {
	jl_errorf("fatal error: sigaction: %s", strerror(errno));
	}
	#else
	if (sigaction(SIGUSR1, &act_die, NULL) < 0) {
	jl_errorf("fatal error: sigaction: %s", strerror(errno));
	}
	#endif

[vtjnash]

It is not really a problem, in that our signal handler thread actually needs them to be set to something in order to be allowed to block them (see the comment there). Signal handling in posix is a bit of a disaster.