Just to make it clear, this is an immediate solution that is good enough to fix the bug. However, a more proper solution would be to introduce the _Alignas concept to EDK II. I would suggest the following macro in Base.h:
/**
Enforce custom alignment for a variable definition.
Similar to C11 alignas macro from stdalign.h, except it must be functional to support MSVC.
@param Alignment Numeric alignment to require.
**/