This patch adds QSPI boot support for LS1021AQDS/TWR board.
The QSPI boot image need to be programmed into the QSPI flash
first. Then the booting will start from QSPI memory space.
Signed-off-by: Alison Wang <alison.wang@freescale.com>
Reviewed-by: York Sun <yorksun@freescale.com>