update qt build shell script and update busybox configure file. fix bugs

guowenxue

2019-08-05 7db66f313c397c80a2aa29a1316b241c988194da

linux-bsp/tarballs/linux-at91.tar.xz does not exist in tree 5b704cdfec88e78a7ad8c00c07ebc56da273daee