Android: Use generic functions in CreateAndroidManifestwizard

The only really qmake specific one was adding files to a project
node, that's now done using the usual *QtSupport indirection.

Change-Id: Id6f011d4b26eaba1cd3943f0089fc5b913193fb7
Reviewed-by: Vikas Pachdha <vikas.pachdha@qt.io>

src/plugins/android/androidqtsupport.h

@@ -81,6 +81,9 @@ public:
     virtual bool validParse(const ProjectExplorer::Target *target) const = 0;
     virtual bool extraLibraryEnabled(const ProjectExplorer::Target *target) const = 0;
     virtual Utils::FileName projectFilePath(const ProjectExplorer::Target *target) const = 0;
+
+    virtual void addFiles(const ProjectExplorer::Target *target, const QString &buildKey,
+                          const QStringList &addedFiles) const = 0;
 };
 
 } // namespace Android