Terminate the string before relying on strlen

Its a c-string we put, so it must be null-terminated.

Signed-off-by: Anton Lundin <glance@acc.umu.se>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

save-xml.c

@@ -191,7 +191,7 @@ static void show_location(struct membuffer *b, struct dive *dive)
 
 		len += format_location(buffer + len, latitude, longitude);
 		if (!dive->location) {
-			memcpy(buffer + len, "/>\n", 4);
+			memcpy(buffer + len, "/>\n\0", 5);
 			put_string(b, buffer);
 			return;
 		}