UEFI Capsule HOB updating includes:

1. add BuildCapsuleHob() in HobLib.h
2. add related APIs implementation in hob library instances.


git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@9378 6f19259b-4bc3-4df7-8a09-765794883524

MdePkg/Library/DxeCoreHobLib/HobLib.c

@@ -528,3 +528,28 @@ BuildMemoryAllocationHob (
   //
   ASSERT (FALSE);
 }
+
+/**
+  Builds an UEFI Capsule HOB.
+
+  This function builds an UEFI Capsule HOB.
+  It can only be invoked during PEI phase;
+  for DXE phase, it will ASSERT() since PEI HOB is read-only for DXE phase.
+  If there is no additional space for HOB creation, then ASSERT().
+
+  @param  BaseAddress   The physical memory-mapped base address of an UEFI capsule.
+  @param  Length        The length of the contiguous memory in bytes.
+
+**/
+VOID
+EFIAPI
+BuildCapsuleHob (
+  IN EFI_PHYSICAL_ADDRESS        BaseAddress,
+  IN UINT64                      Length
+  )
+{
+  //
+  // PEI HOB is read only for DXE phase
+  //
+  ASSERT (FALSE);
+}