smdk6410: add network support

Signed-off-by: Fudong Bai <fudongbai@gmail.com>
smdk6410: add dm9000 support

Signed-off-by: Fudong Bai <fudongbai@gmail.com>
 smdk6410: add dm9000 log

Signed-off-by: Fudong Bai <fudongbai@gmail.com>