For BdsDxe module,

1. Fix the risk that local variable is pointed by global pointer, which may be used outside the variable scope.
2. Add more checking for pointers.

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@10536 6f19259b-4bc3-4df7-8a09-765794883524

IntelFrameworkModulePkg/Universal/BdsDxe/Hotkey.c

@@ -2,7 +2,7 @@
   Provides a way for 3rd party applications to register themselves for launch by the
   Boot Manager based on hot key
 
-Copyright (c) 2007 - 2008, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2007 - 2010, Intel Corporation. All rights reserved.<BR>
 This program and the accompanying materials
 are licensed and made available under the terms and conditions of the BSD License
 which accompanies this distribution.  The full text of the license may be found at
@@ -132,6 +132,7 @@ RegisterHotkey (
                    &gEfiGlobalVariableGuid,
                    &TempOptionSize
                    );
+    ASSERT (TempOption != NULL);
 
     if (CompareMem (TempOption, KeyOption, TempOptionSize) == 0) {
       //