MdeModulePkg/CapsulePei: Optimize the CapsulePei

MdeModulePkg/CapsulePei: Optimize the CapsulePei

REF: https://bugzilla.tianocore.org/show_bug.cgi?id=1853

Code change form Mu project:
https://github.com/microsoft/mu_basecore/blob/release/201903/
MdeModulePkg/Universal/CapsulePei/UefiCapsule.c#L801

Separate the capsule check function from GetCapsuleDescriptors
to AreCapsulesStaged. The original one is unclear.

Avoid querying the capsule variable twice. Use a fixed array
to cache the SG list during count the number of SG list. Then
allocate memory buffer to save the SG list from array.

Using MemoryAllocationLib instead of memory function in Pei
services.

Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao A Wu <hao.a.wu@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Cc: Sean Brogan <sean.brogan@microsoft.com>
Cc: Michael Turner <Michael.Turner@microsoft.com>
Cc: Bret Barkelew <Bret.Barkelew@microsoft.com>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Signed-off-by: Zhichao gao <zhichao.gao@intel.com>
Reviewed-by: Leif Lindholm <leif.lindholm@linaro.org>
Reviewed-by: Hao A Wu <hao.a.wu@intel.com>