Added a fix for a programming bug in Dirt Racer (Europe)

The game relies on uninitialized memory containing certain values.
The game will periodically freeze at boot even on real hardware.
This commit adds a workaround to allow the game to always boot.

bsnes/emulator/game.hpp

@@ -37,6 +37,7 @@ struct Game {
   string sha256;
   string label;
   string name;
+  string title;
   string region;
   string revision;
   string board;
@@ -50,6 +51,7 @@ auto Game::load(string_view text) -> void {
   sha256 = document["game/sha256"].text();
   label = document["game/label"].text();
   name = document["game/name"].text();
+  title = document["game/title"].text();
   region = document["game/region"].text();
   revision = document["game/revision"].text();
   board = document["game/board"].text();

bsnes/sfc/cartridge/cartridge.cpp

@@ -65,6 +65,7 @@ auto Cartridge::load() -> bool {
   if(auto fp = platform->open(ID::SuperFamicom, "manifest.bml", File::Read, File::Required)) {
     game.load(fp->reads());
   } else return false;
+
   loadCartridge(game.document);
 
   //Game Boy

bsnes/sfc/cartridge/cartridge.hpp

@@ -1,6 +1,7 @@
 struct Cartridge {
   auto pathID() const -> uint { return information.pathID; }
   auto region() const -> string { return information.region; }
+  auto headerTitle() const -> string { return game.title; }
 
   auto hashes() const -> vector<string>;
   auto manifests() const -> vector<string>;

bsnes/sfc/cpu/cpu.cpp

@@ -96,6 +96,13 @@ auto CPU::power(bool reset) -> void {
 
   if(!reset) random.array(wram, sizeof(wram));
 
+  //Dirt Racer (Europe) relies on uninitialized memory containing certain values to boot without freezing.
+  //the game itself is broken and will fail to run sometimes on real hardware, but for the sake of expedience,
+  //WRAM is initialized to a constant value that will allow this game to always boot in successfully.
+  if(cartridge.headerTitle() == "DIRT RACER") {
+    for(auto& byte : wram) byte = 0xff;
+  }
+
   for(uint n : range(8)) {
     channels[n] = {};
     if(n != 7) channels[n].next = channels[n + 1];