[AVL6211] DVB-API v5 Support

Fix AVL6211_Read_Signal_Strength / AVL6211_Read_Snr
[0% - 100%] => [0 - 65535]
Fix AVL6211_Set_Frontend
Fix frontend capabilities / frontent calls
Merge pull request #7 from SmartHD/patch-1

[AVL6211] DVB-API v5 Support