cmInstall*Generator: std::string params

Several construction parameters converted to std::string
Also made a few class members const

Source/cmInstallTargetGenerator.h

@@ -23,11 +23,11 @@ class cmInstallTargetGenerator : public cmInstallGenerator
 {
 public:
   cmInstallTargetGenerator(
-    std::string targetName, const char* dest, bool implib,
-    const char* file_permissions,
-    std::vector<std::string> const& configurations, const char* component,
-    MessageLevel message, bool exclude_from_all, bool optional,
-    cmListFileBacktrace backtrace = cmListFileBacktrace());
+    std::string targetName, std::string const& dest, bool implib,
+    std::string file_permissions,
+    std::vector<std::string> const& configurations,
+    std::string const& component, MessageLevel message, bool exclude_from_all,
+    bool optional, cmListFileBacktrace backtrace = cmListFileBacktrace());
   ~cmInstallTargetGenerator() override;
 
   /** Select the policy for installing shared library linkable name
@@ -106,13 +106,13 @@ protected:
                                const std::string& toDestDirPath);
   void IssueCMP0095Warning(const std::string& unescapedRpath);
 
-  std::string TargetName;
+  std::string const TargetName;
   cmGeneratorTarget* Target;
-  std::string FilePermissions;
+  std::string const FilePermissions;
   NamelinkModeType NamelinkMode;
-  bool ImportLibrary;
-  bool Optional;
-  cmListFileBacktrace Backtrace;
+  bool const ImportLibrary;
+  bool const Optional;
+  cmListFileBacktrace const Backtrace;
 };
 
 #endif