[ARM] 4980/1: [AT91] emQbit ECB_AT91 board support

Support for the emQbit ECB_AT91 board.
  <http://wiki.emqbit.com/free-ecb-at91

>

Original patch from Nelson Castillo.

Signed-off-by: Andrew Victor <linux@maxim.org.za>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>