IntelFsp2Pkg: Add function to get FspInfoHeader before stack is ready

IntelFsp2Pkg: Add function to get FspInfoHeader before stack is ready

we need to locate the FSP Info Header before the stack is initialized to
access the cfg region for any UPD. Hence adding the
AsmGetFspInfoHeaderNoStack function to support it.

Note: This function is there in IntelFspPkg but got removed in IntelFsp2Pkg

Cc: Maurice Ma <maurice.ma@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Giri P Mudusuru <giri.p.mudusuru@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Satya Yarlagadda <satya.p.yarlagadda@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Giri P Mudusuru <giri.p.mudusuru@intel.com>