ArmPlatformPkg: Fix stack switch bug after commit 7945b29

ArmPlatformPkg: Fix stack switch bug after commit 7945b29

This is the complementary patch for the commit 7945b29, which strictly
aligns temporary heap size and temporary stack size, but does not do
the same thing when switching stack and heap to permanent memory, and
then it may cause fatal data corruption like PHIT HOB lost and stack
pointer unaligned.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Heyi Guo <heyi.guo@linaro.org>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@19213 6f19259b-4bc3-4df7-8a09-765794883524