Access std::ios_base with std::ios

Just because it is shorter.

Source/CPack/cmCPackDragNDropGenerator.cxx

@@ -235,7 +235,7 @@ bool cmCPackDragNDropGenerator::CreateEmptyFile(std::ostringstream& target,
     return false;
   } else {
     // Seek to desired size - 1 byte
-    fout.seekp(size - 1, std::ios_base::beg);
+    fout.seekp(size - 1, std::ios::beg);
     char byte = 0;
     // Write one byte to ensure file grows
     fout.write(&byte, 1);

Source/cmGlobalNinjaGenerator.cxx

@@ -513,8 +513,8 @@ void cmGlobalNinjaGenerator::Generate()
   this->WriteBuiltinTargets(*this->BuildFileStream);
 
   if (cmSystemTools::GetErrorOccuredFlag()) {
-    this->RulesFileStream->setstate(std::ios_base::failbit);
-    this->BuildFileStream->setstate(std::ios_base::failbit);
+    this->RulesFileStream->setstate(std::ios::failbit);
+    this->BuildFileStream->setstate(std::ios::failbit);
   }
 
   this->CloseCompileCommandsStream();

Source/cmMakefile.cxx

@@ -3387,7 +3387,7 @@ int cmMakefile::ConfigureFile(const char* infile, const char* outfile,
     }
   } else {
     std::string newLineCharacters;
-    std::ios_base::openmode omode = std::ios_base::out | std::ios_base::trunc;
+    std::ios::openmode omode = std::ios::out | std::ios::trunc;
     if (newLine.IsValid()) {
       newLineCharacters = newLine.GetCharacters();
       omode |= std::ios::binary;