Include <stdlib.h> for exit() and abort() prototypes.

Approved by:	das (mentor)

libexec/rexecd/rexecd.c

@@ -59,6 +59,7 @@ static const char rcsid[] =
 #include <signal.h>
 #include <stdarg.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
 #include <syslog.h>
 #include <unistd.h>

usr.sbin/atm/scspd/scspd.c

@@ -55,6 +55,7 @@
 #include <libatm.h>
 #include <paths.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
 #include <syslog.h>
 #include <unistd.h>

usr.sbin/rpc.ypupdated/yp_dbupdate.c

@@ -36,6 +36,7 @@ __FBSDID("$FreeBSD$");
 #include <sys/fcntl.h>
 
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
 #include <errno.h>
 #include <limits.h>