IXDP425 NAND support (arch specific part).

The generic platform driver that is used by ixdp425 platfrom is already
in upstream kernel in 2.6.22-rc1.
Signed-off-by: NVladimir Barinov <vbarinov@ru.mvista.com>
Signed-off-by: NRuslan Sushko <rsushko@ru.mvista.com>
Signed-off-by: NDeepak Saxena <dsaxena@mvista.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>