Remove decode button from MMC.

DiscImageChef.Server/Areas/Admin/Controllers/MmcController.cs

@@ -1,4 +1,3 @@
-using System;
 using System.Linq;
 using System.Threading.Tasks;
 using DiscImageChef.CommonTypes.Metadata;
@@ -80,8 +79,6 @@ namespace DiscImageChef.Server.Areas.Admin.Controllers
             return RedirectToAction(nameof(Index));
         }
 
-        public IActionResult Decode(int id) => throw new NotImplementedException();
-
         public async Task<IActionResult> Clean()
         {
             _context.Mmc.RemoveRange(_context.Mmc.Where(m => m.FeaturesId == null && m.ModeSense2AData == null));