video: atmel/lcd: add LCD driver for new Atmel SoC

The new Atmel SoC (at91sam9x5 series and at91sam9n12) add a totally
different LCD controller. Add this new driver to support it.

Using CONFIG_ATMEL_HLCD (distinguish with CONFIG_ATMEL_LCD) to enable
this in board configuration file.

Signed-off-by: Bo Shen <voice.shen@atmel.com>
Signed-off-by: Anatolij Gustschin <agust@denx.de>