Remove extra flag to sudo_sigaction(). We want to trap the signal

regardless of whether or not it is ignored by the underlying command
since there's no way to know what signal handlers the command will
install.  Now we just use sudo_sigaction() to set a flag in
saved_signals[] to indicate whether a signal needs to be restored
before exec.

src/sudo.h

@@ -267,7 +267,7 @@ char *get_process_ttyname(void);
 /* signal.c */
 struct sigaction;
 extern int signal_pipe[2];
-int sudo_sigaction(int signo, struct sigaction *sa, struct sigaction *osa, bool update_only);
+int sudo_sigaction(int signo, struct sigaction *sa, struct sigaction *osa);
 void init_signals(void);
 void restore_signals(void);
 void save_signals(void);