Fix division by zero possibility during frame matching.

src/hle/rt64_game_frame.cpp

@@ -646,8 +646,13 @@ namespace RT64 {
             }
             
             auto modulo = [](int a, int b) {
+                if (b != 0) {
                     int r = a % b;
                     return r < 0 ? r + b : r;
+                }
+                else {
+                    return 0;
+                }
             };
 
             const float deltaUls = curTile.uls - prevTile.uls;