Add more NDS extensions

srl -> "official" DS rom extension (generally found in prototypes etc)
dsi -> used for DSi only games
ids -> used for iQue DS games

upstream handles all these rom extensions already

src/BizHawk.Client.Common/RomLoader.cs

@@ -874,7 +874,7 @@ private static class RomFileExtensions
 
 			public static readonly IReadOnlyCollection<string> N64DD = new[] { "ndd" };
 
-			public static readonly IReadOnlyCollection<string> NDS = new[] { "nds" };
+			public static readonly IReadOnlyCollection<string> NDS = new[] { "nds", "srl", "dsi", "ids" };
 
 			public static readonly IReadOnlyCollection<string> NES = new[] { "nes", "fds", "unf" };