Add support for Xilinx SystemACE CompactFlash interface

Tested on Xilinx Virtex ppc405, Katmai 440SPe, and Microblaze

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Stefan Roese <sr@denx.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: John William <jwilliams@itee.uq.edu.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>