[ARM] 5338/1: Add Nuvoton W90P910 Platform support

Add Nuvoton W90X900 ARM9 plat support to linux arm tree,
Now, this patch include only W90P910 EVB of W90P910 CPU,
Its driver is nothing.

Signed-off-by: Wan ZongShun <mcuos.com@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>