MdeModulePkg/DxeCapsuleLibFmp: Verify nested capsule with FMP

MdeModulePkg/DxeCapsuleLibFmp: Verify nested capsule with FMP

https://bugzilla.tianocore.org/show_bug.cgi?id=873

Update IsNestedFmpCapsule() to verify the CapsuleGuid in
the CapsuleHeader against the installed Firmware Management
Protocol instances.  The current logic that uses the ESRT
Table does not work because capsules are processed before
the ESRT Table is published at the Ready To Boot event.

Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Cc: Eric Dong <eric.dong@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Michael D Kinney <michael.d.kinney@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Reviewed-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Bret Barkelew <Bret.Barkelew@microsoft.com>