Add openssh build shell script, can ssh logon but not support sftp

guowenxue

2019-08-08 0ee3336a011e39edb4280177755cce0807011ac0

linux-bsp/tarballs/linux-at91.tar.xz does not exist in tree 6b4b29be93abed7f1550e29560fe99246d76dd10