candump: reserve enough space for ctrlmsg

The ctrlmsg must be large enough to contains 3 elements of various
sizes, not a single element of the sum of the size.

Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>

candump.c

@@ -303,7 +303,9 @@ int main(int argc, char **argv)
 	int join_filter;
 	char *ptr, *nptr;
 	struct sockaddr_can addr;
-	char ctrlmsg[CMSG_SPACE(sizeof(struct timeval) + 3 * sizeof(struct timespec) + sizeof(__u32))];
+	char ctrlmsg[CMSG_SPACE(sizeof(struct timeval)) +
+		     CMSG_SPACE(3 * sizeof(struct timespec)) +
+		     CMSG_SPACE(sizeof(__u32))];
 	struct iovec iov;
 	struct msghdr msg;
 	struct cmsghdr *cmsg;