fix sigsuspend syscall

src/signal/sigsuspend.c

@@ -3,5 +3,5 @@
 
 int sigsuspend(const sigset_t *mask)
 {
-	return syscall2(__NR_rt_sigsuspend, (long)mask, sizeof(sigset_t));
+	return syscall2(__NR_rt_sigsuspend, (long)mask, SYSCALL_SIGSET_SIZE);
 }