Add support for SAMA5D3 Xplained board and options to select & build
u-boot configs for different media storage.
Signed-off-by: Sandeep Sheriker Mallikarjun <sandeepsheriker.mallikarjun@microchip.com>
Adds u-boot for the at91 platform and a couple of boards.
The build honours COPTS to benefit from fortify source et al.
Signed-off-by: Ben Whitten <ben.whitten@gmail.com>