STYLE: fixed misspellings of Mac OS X

Source/kwsys/SystemTools.cxx

@@ -3603,7 +3603,7 @@ kwsys_stl::string SystemTools::MakeCindentifier(const char* s)
   return str;
 }
 
-// Due to a buggy stream library on the HP and another on Mac OSX, we
+// Due to a buggy stream library on the HP and another on Mac OS X, we
 // need this very carefully written version of getline.  Returns true
 // if any data were read before the end-of-file was reached.
 bool SystemTools::GetLineFromStream(kwsys_ios::istream& is,

Source/kwsys/SystemTools.hxx.in

@@ -427,7 +427,7 @@ public:
   
   /**
    * Read line from file. Make sure to get everything. Due to a buggy stream
-   * library on the HP and another on Mac OSX, we need this very carefully
+   * library on the HP and another on Mac OS X, we need this very carefully
    * written version of getline. Returns true if any data were read before the
    * end-of-file was reached. If the has_newline argument is specified, it will
    * be true when the line read had a newline character.