arm: socfpga: add cyclone5 based de10-nano board

Add support for the Terasic DE10-Nano board.  The board
is based on the DE0-Nano-Soc board but adds a larger FPGA
and an HDMI output.

Signed-off-by: Dalon Westergreen <dwesterg@gmail.com>
Reviewed-by: Dinh Nguyen <dinguyen@kernel.org>