Add iOS platform (refactor Mac into shared Apple platform impl)

Source/Editor/Cooker/Steps/CompileScriptsStep.cpp

@@ -208,6 +208,10 @@ bool CompileScriptsStep::Perform(CookingData& data)
         platform = TEXT("Mac");
         architecture = TEXT("ARM64");
         break;
+    case BuildPlatform::iOSARM64:
+        platform = TEXT("iOS");
+        architecture = TEXT("ARM64");
+        break;
     default:
         LOG(Error, "Unknown or unsupported build platform.");
         return true;

Source/Editor/Cooker/Steps/CookAssetsStep.cpp

@@ -534,6 +534,14 @@ bool ProcessShaderBase(CookAssetsStep::AssetCookData& data, ShaderAssetBase* ass
         COMPILE_PROFILE(Vulkan_SM5, SHADER_FILE_CHUNK_INTERNAL_VULKAN_SM5_CACHE);
         break;
     }
+#endif
+#if PLATFORM_TOOLS_IOS
+    case BuildPlatform::iOSARM64:
+    {
+        const char* platformDefineName = "PLATFORM_IOS";
+        COMPILE_PROFILE(Vulkan_SM5, SHADER_FILE_CHUNK_INTERNAL_VULKAN_SM5_CACHE);
+        break;
+    }
 #endif
     default:
     {