Convert macros from plain QByteArray to a vector of structs

The old code model expected the macros as C++ formatted text
("#define Foo 42) but newer targets like the Clang codemodel expect key
value arguments like "-DFoo=42". So instead of parsing the text again and
again we use an abstract data description.

Task-number: QTCREATORBUG-17915
Change-Id: I0179fd13c48a581e91ee79bba9d42d501c26f19f
Reviewed-by: Tobias Hunger <tobias.hunger@qt.io>

src/plugins/cmakeprojectmanager/servermodereader.h

@@ -86,7 +86,7 @@ private:
 
         Target *target = nullptr;
         QString compileFlags;
-        QStringList defines;
+        ProjectExplorer::Macros macros;
         QList<IncludePath *> includePaths;
         QString language;
         QList<Utils::FileName> sources;