In current code, when adding string package, it will return 'gStringPackHandle'. But the code use the 'gHiiHandle' to get string. It is incorrect. This patch is to fix this issue. Cc: Eric Dong <eric.dong@intel.com> Contributed-under: TianoCore Contribution Agreement 1.0 Signed-off-by: Dandan Bi <dandan.bi@intel.com> Reviewed-by: Eric Dong <eric.dong@intel.com>