luna-sysmgr: update support of a500 (hybris migration)


Signed-off-by: Christophe Chapuis <chris.chapuis@gmail.com>
webappmanager: update support for a500 (hybris migration)

  * remove old use-minimal-qpa.patch file, now unused upstream
  * use a dedicated patch for a500 support
  * activate hybris and qt-webos-plugin for WAM


Signed-off-by: Christophe Chapuis <chris.chapuis@gmail.com>