Rebuild atlas_sdcard_v1.1.img from sources

[gmacario]

See related #8

Create documentation in https://github.com/SOLARMA/try-atlas-soc/wiki/Rebuilding-atlas_sdcard_1.1.img-from-sources

[hshcc]

你好，还有文件吗？

[hshcc]

你好，还有atlas_sdcard_v1.1.img这个文件吗？