Remove unused coin attributes from finalclass and warpclass

Looks like coins were basically a scrapped mechanic, although I'm not
sure what these attributes were for. I guess counting the number of
coins in each room? But why, when you can just make a function to count
them automatically? Whatever.

desktop_version/src/Finalclass.h

@@ -12,7 +12,7 @@ public:
     const int* loadlevel(int rx, int ry);
 
     std::string roomname;
-    int coin, rcol;
+    int rcol;
     bool warpx, warpy;
 };