BeagleBoard: Update documentation

- Update build instructions
- Add instructions to test UEFI on qEmu either using the NOR flash or the SD card



git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@11997 6f19259b-4bc3-4df7-8a09-765794883524
1 file changed