VS: switch to new folder structure while keeping the old one working

Fixes: #21170
diff --git a/Source/cmGlobalVisualStudio10Generator.h b/Source/cmGlobalVisualStudio10Generator.h
index 5e42c17..e221d4c 100644
--- a/Source/cmGlobalVisualStudio10Generator.h
+++ b/Source/cmGlobalVisualStudio10Generator.h
@@ -78,6 +78,13 @@
   const char* GetPlatformToolsetCudaCustomDir() const;
   std::string const& GetPlatformToolsetCudaCustomDirString() const;
 
+  /** The nvcc subdirectory of a custom cuda install directory */
+  std::string const& GetPlatformToolsetCudaNvccSubdirString() const;
+
+  /** The visual studio integration subdirectory of a custom cuda install
+   * directory */
+  std::string const& GetPlatformToolsetCudaVSIntegrationSubdirString() const;
+
   /** Return whether we need to use No/Debug instead of false/true
       for GenerateDebugInformation.  */
   bool GetPlatformToolsetNeedsDebugEnum() const
@@ -188,6 +195,8 @@
   std::string GeneratorToolsetCustomVCTargetsDir;
   std::string GeneratorToolsetCuda;
   std::string GeneratorToolsetCudaCustomDir;
+  std::string GeneratorToolsetCudaNvccSubdir;
+  std::string GeneratorToolsetCudaVSIntegrationSubdir;
   std::string DefaultPlatformToolset;
   std::string DefaultPlatformToolsetHostArchitecture;
   std::string DefaultAndroidToolset;