[U-Boot] [ANNOUNCE] U-Boot driver model repo

[TigerLiu at via-alliance.com]

Hi, Simon:
I git cloned http://git.denx.de/u-boot-dm.git .
And followed these steps to compile it:
   make sandbox_config
   make

but failed:
arch/sandbox/cpu/sdl.c:10:21: error: sdl/sdl.h: No such file or directory

Best wishes,