cmGeneratedFileStream: clang-tidy applied to remove redundant ``c_str`` calls

After changing the ``cmGeneratedFileStream`` methods to accept
``std::string const&`` instead of ``const char*`` we don't
need to call ``std::string::c_str`` anymore when passing
a ``std::string`` to a ``cmGeneratedFileStream`` method.

This patch removes all redundant ``std::string::c_str``
calls when passing a string to a ``cmGeneratedFileStream`` method.

It was generated by building CMake with clang-tidy enabled using
the following options:

-DCMAKE_CXX_CLANG_TIDY=/usr/bin/clang-tidy-4.0;-checks=-*,readability-redundant-string-cstr;-fix;-fix-errors

1 files changed, 2 insertions, 2 deletions

diff --git a/Source/cmLocalGenerator.cxx b/Source/cmLocalGenerator.cxx
index a669477..2660791 100644
--- a/Source/cmLocalGenerator.cxx
+++ b/Source/cmLocalGenerator.cxx
@@ -253,7 +253,7 @@ void cmLocalGenerator::GenerateTestFiles()
   file += "/";
   file += "CTestTestfile.cmake";
 
-  cmGeneratedFileStream fout(file.c_str());
+  cmGeneratedFileStream fout(file);
   fout.SetCopyIfDifferent(true);
 
   fout << "# CMake generated Testfile for " << std::endl
@@ -429,7 +429,7 @@ void cmLocalGenerator::GenerateInstallRules()
     toplevel_install = 1;
   }
   file += "/cmake_install.cmake";
-  cmGeneratedFileStream fout(file.c_str());
+  cmGeneratedFileStream fout(file);
   fout.SetCopyIfDifferent(true);
 
   // Write the header.