The exclusive load/store instructions don't work well when MMU and cache
are disabled on some cores e.g. Cortex-A72. Change it to voting lock[1]
to select the primary core when multi-cores boot simultaneously.
The voting lock has reasonable but minimal requirements on the memory
system.
[1] https://www.kernel.org/doc/html/next/arch/arm/vlocks.html
Signed-off-by: Jaxson Han <jaxson.han@arm.com>
7904c6f0f3