download.json: remove firmware_ls1021atwr_uboot_qspiboot.img
download.json: remove firmware_ls1021atwr_uboot_qspiboot.img

Signed-off-by: Zhenhua Luo <e3b50d6ec33f2b6a2b4ae5cb4a4d190eb294b1a1@nxp.com>

lsdk/lsdk.github.io,lsdk/lsdk.github.io