armv7: LS1021a: enable i-cache in start.S

Delete CONFIG_SKIP_LOWLEVEL_INIT define in ls1021atwr.h and
ls1021aqds.h can let it run cpu_init_cp15 to enable i-cache. First
stage of u-boot can run faster after that. There is a description
about skip lowlevel init in board/freescale/ls1021atwr/README.

Signed-off-by: Xiaoliang Yang <xiaoliang.yang@nxp.com>
Reviewed-by: York Sun <york.sun@nxp.com>
6 files changed