Add msdfgen build for iOS and Mac

Source/ThirdParty/msdfgen/msdfgen.Build.cs

@@ -34,6 +34,7 @@ public class msdfgen : DepsModule
             break;
         case TargetPlatform.Linux:
         case TargetPlatform.Mac:
+        case TargetPlatform.iOS:
         case TargetPlatform.Android:
             options.OutputFiles.Add(Path.Combine(depsRoot, "libmsdfgen-core.a"));
             break;

Source/Tools/Flax.Build/Deps/Dependencies/msdfgen.cs

@@ -34,6 +34,7 @@ namespace Flax.Deps.Dependencies
                     return new[]
                     {
                         TargetPlatform.Mac,
+                        TargetPlatform.iOS,
                     };
                 default: return new TargetPlatform[0];
                 }