Since we use SPEED GRADE fuse to set A55 frequency, remove the
set_arm_core_low_drive_clk function which has hard coded frequency.
And adjust clock_init called sequence and split it to early and late
functions.
Set the authen register in early function, because CCF driver checks
NS bit.
Set bus and core clock in late function, because the fuse read and
SoC type/rev depend on ELE.

Reviewed-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Ye Li <ye.li@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>