armv8: start.S: Subordinate CPUs psci setup vector

As current design, only Manager CPU called armv8_setup_psci() before
jump to next stage(such as Linux Kernel), Subordinate CPUs also need
setup psci vector to handle trap request which comes from higher EL
level.

Signed-off-by: Xu Zhang <423756212@qq.com>
[trini: Guard with !CONFIG_XPL_BUILD check]
1 file changed