fix mupen dll not to have 100 frame hack crash; change c# side to more visibly hang (the frame counter stops, so the condition can be detected)

BizHawk.Emulation.Cores/Consoles/Nintendo/N64/N64.cs

@@ -256,7 +256,8 @@ namespace BizHawk.Emulation.Cores.Nintendo.N64
 				LagCount++;
 			}
 
-			Frame++;
+			if(!api.IsCrashed)
+				Frame++;
 		}
 
 		public string SystemId { get { return "N64"; } }

BizHawk.Emulation.Cores/Consoles/Nintendo/N64/NativeApi/mupen64plusCoreApi.cs

@@ -572,6 +572,8 @@ namespace BizHawk.Emulation.Cores.Nintendo.N64.NativeApi
 
 		volatile bool emulator_running = false;
 
+		public bool IsCrashed => !emulator_running;
+
 		/// <summary>
 		/// Starts executing the emulator asynchronously
 		/// Waits until the emulator booted up and than returns