ARM: dts: sti: Introduce 4KOpen (stih418-b2264) board

4KOpen (B2264) is a board based on the STMicroelectronics STiH418 soc:
  - 2GB DDR
  - HDMI
  - Ethernet 1000-BaseT
  - PCIe (mini PCIe connector)
  - MicroSD slot
  - USB2 and USB3 connectors
  - Sata
  - 40 pins GPIO header

Signed-off-by: Alain Volmat <avolmat@me.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
Signed-off-by: Patrice Chotard <patrice.chotard@foss.st.com>