cmGeneratorTarget: Use enum for GetType.

Source/cmGeneratorTarget.cxx

@@ -323,7 +323,7 @@ cmLocalGenerator* cmGeneratorTarget::GetLocalGenerator() const
 }
 
 //----------------------------------------------------------------------------
-int cmGeneratorTarget::GetType() const
+cmState::TargetType cmGeneratorTarget::GetType() const
 {
   return this->Target->GetType();
 }

Source/cmGeneratorTarget.h

@@ -41,7 +41,7 @@ public:
   cmComputeLinkInformation*
     GetLinkInformation(const std::string& config) const;
 
-  int GetType() const;
+  cmState::TargetType GetType() const;
   std::string GetName() const;
   const char *GetProperty(const std::string& prop) const;
   bool GetPropertyAsBool(const std::string& prop) const;