options/posix: Fix implicit fallthrough warning
@@ -436,6 +436,7 @@ int lockf(int fd, int op, off_t size) {
return -1;
case F_ULOCK:
l.l_type = F_UNLCK;
+ [[fallthrough]];
case F_TLOCK:
return fcntl(fd, F_SETLK, &l);
case F_LOCK:
