[U-Boot] [U-boot] Some questions about BootStage functions

[TigerLiu at viatech.com.cn]

Hi, Simon:
Got it!
Thanks!
My codebase is 2013.04 release version.
It seemed board_f.c / board_r.c had been moved to common directory.
Arch/Arm/Lib/Board.c  would be compiled conditionally.

Best wishes,