Ignoring SIGCHLD causes a race leading to the occasional hang of init

when init will wait() on itself in waitfor() when the child exits before
init is scheduled to run.  Letting init hang is very seriously bad.
 -Erik

init/init.c

@@ -1063,7 +1063,6 @@ extern int init_main(int argc, char **argv)
 	signal(SIGCONT, cont_handler);
 	signal(SIGSTOP, stop_handler);
 	signal(SIGTSTP, stop_handler);
-	signal(SIGCHLD, SIG_IGN);
 
 	/* Turn off rebooting via CTL-ALT-DEL -- we get a 
 	 * SIGINT on CAD so we can shut things down gracefully... */