cmState: Move CacheEntryType enum to separate namespace

Port dependent code to the change.

Source/cmake.h

@@ -161,7 +161,7 @@ public:
   ///! Break up a line like VAR:type="value" into var, type and value
   static bool ParseCacheEntry(const std::string& entry, std::string& var,
                               std::string& value,
-                              cmState::CacheEntryType& type);
+                              cmStateEnums::CacheEntryType& type);
 
   int LoadCache();
   bool LoadCache(const std::string& path);