Refactor: Use fullmap() everywhere

This replaces all instances of unlocking all rooms on the map with calls
to map.fullmap(), for consistency.

This also fixes two comments that got swapped around in startgamemode().
I don't know how that happened.

[skip ci]

desktop_version/src/Script.cpp

@@ -1437,7 +1437,7 @@ void scriptclass::run(void)
             {
                 game.unlocknum(Unlock_SECRETLAB);
                 game.insecretlab = true;
-                SDL_memset(map.explored, true, sizeof(map.explored));
+                map.fullmap();
             }
             else if (words[0] == "leavesecretlab")
             {
@@ -2746,7 +2746,7 @@ void scriptclass::startgamemode(const enum StartMode mode)
         {
             game.timetrialcountdown = 0;
             game.timetrialparlost = true;
-            SDL_memset(map.explored, true, sizeof(map.explored));
+            map.fullmap();
         }
 
         graphics.fademode = FADE_START_FADEIN;
@@ -2756,9 +2756,9 @@ void scriptclass::startgamemode(const enum StartMode mode)
         game.startspecial(0);
 
         /* Unlock the entire map */
-        SDL_memset(obj.collect, true, sizeof(obj.collect[0]) * 20);
+        map.fullmap();
         /* Give all 20 trinkets */
-        SDL_memset(map.explored, true, sizeof(map.explored));
+        SDL_memset(obj.collect, true, sizeof(obj.collect[0]) * 20);
         i = 400; /* previously a nested for-loop set this */
         game.insecretlab = true;
         map.showteleporters = true;