arm: at91: add at91sam9n12ek board support

Add support for following features:
  - nand boot, with PMECC 2bit ECC for 512 bytes sector
  - SPI flash boot
  - SD card boot
  - LCD support

Signed-off-by: Josh Wu <josh.wu@atmel.com>
[fix -Wimplicit-function-declaration for at91_lcd_hw_init()]
Signed-off-by: Andreas Bießmann <andreas.devel@googlemail.com>
9 files changed