UefiCpuPkg/CpuFeatures: Export HOB if CPU initialized in PEI

UefiCpuPkg/CpuFeatures: Export HOB if CPU initialized in PEI

In current implementation, CPU initialized can be done in PEI
or DXE phase. PEI uses CpuFeaturesPei and Dxe uses CpuFeaturesDxe.
If CPU initialized in PEI phase, CpuFeaturesDxe driver will
not be used. This driver will install gEdkiiCpuFeaturesInitDoneGuid
protocol after it initializes the CPU.

Some drivers depend on this protocol to dispatch themselves. If
CpuFeaturesDxe not been used, these drivers will not be dispatched.

This patch fix the above issue. If Cpu initialized in PEI
phase, it also report a guid HOB for CpuFeaturesDxe.
CpuFeaturesDxe will check this HOB first. If it found this
HOB, it just install gEdkiiCpuFeaturesInitDoneGuid protocol,
else it will also do the CPU initialization.

Cc: Ruiyu Ni <ruiyu.ni@intel.com>
Cc: Laszlo Ersek <lersek@redhat.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>