Patch from Ben Dooks

The current Simtec BAST nand area timings are a little
too slow to be obtained by a 2410 running at 266MHz,
so reduce the timings slightly to bring them into the
acceptable range.
Signed-off-by: NBen Dooks <ben-linux@fluff.org>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>