Update HobLib and PeCoffLib according to MDE Lib Spec 0.61c

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@6100 6f19259b-4bc3-4df7-8a09-765794883524

MdePkg/Library/DxeCoreHobLib/HobLib.c

@@ -23,6 +23,7 @@
 
 /**
   Returns the pointer to the HOB list.
+  ASSERT() if the HOB list returned by GetHobList() is NULL.
 
   This function returns the pointer to first HOB in the list.
 
@@ -35,6 +36,7 @@ GetHobList (
   VOID
   )
 {
+	ASSERT (gHobList != NULL);
   return gHobList;
 }
 
@@ -185,7 +187,6 @@ GetBootModeHob (
   EFI_HOB_HANDOFF_INFO_TABLE    *HandOffHob;
 
   HandOffHob = (EFI_HOB_HANDOFF_INFO_TABLE *) GetHobList ();
-  ASSERT (HandOffHob != NULL);
 
   return  HandOffHob->BootMode;
 }