ARM: dts: imx6ul: segin: Add phyBOARD-Segin with eMMC phyCORE-i.MX6UL

Add a PHYTEC phyBOARD-Segin full featured with phyCORE-i.MX 6UL with
eMMC and following features:
    - i.MX 6UL
    - 512 MB RAM
    - eMMC
    - USB Host/OTG
    - 2x 100 Mbit/s Ethernet
    - RS232
    - CAN

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