Android: Improve "Add new AVD" dialog

* Re-organize the implementation to create a new AVD
* Use SystemImage instead of SdKPlatform because now
an SdkPlatform can be installed partially with a SystemImage.
The current implementation does not consider the this case,
thus we end up with an uncomplete list of installed system images.
* Add Device definitions with categories (phone, tablet, tv, etc.)
to the creation process (check -d arg in avdmanager create avd).

Task-number: QTCREATORBUG-23284
Change-Id: Id02a71ad452fb423fa2781d06ef3fcf2afa328a9
Reviewed-by: Alessandro Portale <alessandro.portale@qt.io>

src/plugins/android/androidsdkpackage.h

@@ -114,10 +114,13 @@ public:
     const QString &abiName() const;
     const SdkPlatform *platform() const;
     void setPlatform(SdkPlatform *platform);
+    int apiLevel() const;
+    void setApiLevel(const int apiLevel);
 
 private:
     QPointer<SdkPlatform> m_platform;
     QString m_abiName;
+    int m_apiLevel = -1;
 };
 using SystemImageList = QList<SystemImage*>;