ArmPlatformPkg/PrePi: Use the same calculation to declare the stack size as in the...

ArmPlatformPkg/PrePi: Use the same calculation to declare the stack size as in the entrypoint

The stack size in the entrypoint (ie: $ARCH/ModuleEntryPoint.S) is calculated such as
StackSize = PrimaryCoreStack + (core_count - 1) * SecondaryCoreStack

While we were declaring the stacksize into the stack hob as:
StackSize = PrimaryCoreStack + (cluster * 8) * SecondaryCoreStack

If the number of cluster (ie: PcdClusterCount) were not defined correctly then
the stack size declaration were not correct.
It could cause stack corruption if the allocator allocates memory in this range.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Olivier Martin <olivier.martin@arm.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@15431 6f19259b-4bc3-4df7-8a09-765794883524