nds32: Enable the function of passing parameters to Linux

Add a header file, setup.h, which copy from Linux source code,
this file contain structures are used to pass initialisation parameters
to Linux. Enable this function on adp-ag101/adp-ag101p target

Signed-off-by: Kuan-Yu Kuo <ken.kuoky@gmail.com>
Cc: Macpaul Lin <macpaul@gmail.com>