C++: update project info once after finishing adding all project parts.

So that recalculating the information is not O(n^2) but linear.

Change-Id: I69903e0b5ad321d071804d782ad634a3f300e71a
Reviewed-by: Daniel Teske <daniel.teske@digia.com>
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@digia.com>

src/plugins/cmakeprojectmanager/cmakeproject.cpp

@@ -350,6 +350,7 @@ bool CMakeProject::parseCMakeLists()
         }
 
         m_codeModelFuture.cancel();
+        pinfo.finish();
         m_codeModelFuture = modelmanager->updateProjectInfo(pinfo);
     }