Fix pointer to data in read anwser packets.
Fix pointer to data in read anwser packets.

AnilRamachandran/aravis,lu-zero/aravis,AravisProject/aravis,AnilRamachandran/aravis,AnilRamachandran/aravis,AnilRamachandran/aravis,AnilRamachandran/aravis,lu-zero/aravis,lu-zero/aravis,AravisProject/aravis,AravisProject/aravis,AravisProject/aravis,lu-zero/aravis,lu-zero/aravis,AravisProject/aravis