ARM: dts: imx6ul: phytec: Add support for optional PEB-AV-02 LCD adapter

The PHYTEC PEB-AV-02 adapter adds the capability to connect a parallel
LCD display to the phyBOARD-Segin full featured, either with capacitive
or resistive touch.

Signed-off-by: Stefan Riedmueller <s.riedmueller@phytec.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>