added device tree sources for more GTA04 variants and prepared for handling different panels and touch screens

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
GTA04b3/L7004: fixed flipped y axis of touch

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
fixed GTA04b3 (L7004) panel

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>
improved device tree again

Signed-off-by: H. Nikolaus Schaller <hns@goldelico.com>