zynq: Add zynq zc70x board support

zynq: Add zynq zc70x board support

The Zynq-7000 APSOC zc702 and zc706 enabled complte embedded
processing includes ASIC and FPGA design.

ZC702-:

APSOC:
- XC7Z020-CLG484-1
Memory:
- DDR3 Component Memory 1GB
- 16MB Quad SPI Flash
- IIC - 1 KB EEPROM
Connectivity:
- Gigabit Ethernet GMII, RGMII and SGMII.
- USB OTG - Host USB
- IIC Bus Headers/HUB
- 1 CAN with Wake on CAN
- USB-UART
Video/Display:
- HDMI Video OUT
- 8X LEDs
Control & I/O:
- 3 User Push Buttons
- 2 User Switches
- 8 User LEDs

For more info on zc702 board:
- http://www.xilinx.com/products/boards-and-kits/EK-Z7-ZC702-G.htm

ZC706-:

APSOC:
- XC7Z045 FFG900 -2 AP SoC
Memory:
- DDR3 Component Memory 1GB (PS)
- DDR3 SODIM Memory 1GB (PL)
- 2X16MB Quad SPI Flash (dual parallel)
- IIC - 1 KB EEPROM
Connectivity:
- PCIe Gen2x4
- SFP+ and SMA Pairs
- GigE RGMII Ethernet (PS)
- USB OTG 1 (PS) - Host USB
- IIC Bus Headers/HUB (PS)
- 1 CAN with Wake on CAN (PS)
- USB-UART
Video/Display:
- HDMI 8 color RGB 4.4.4 1080P-60 OUT
- HDMI IN 8 color RGB 4.4.4
Control & I/O:
- 2 User Push Buttons/Dip Switch, 2 User LEDs
- IIC access to GPIO
- SDIO (SD Card slot)
- 3 User Push Buttons, 2 User Switches, 8 User LEDs

For more info on zc706 board:
- http://www.xilinx.com/products/boards-and-kits/EK-Z7-ZC706-G.htm

Signed-off-by: Jagannadha Sutradharudu Teki <jaganna@xilinx.com>