ShellPkg: Revert git 'd6cf1af9' fix

ShellPkg: Revert git 'd6cf1af9' fix

'd6cf1af9' is associated with '3d0a49ad' commit. So, this patch is
used to respond the revert for '3d0a49ad' to adapt the Ipv4 config
policy update.

Cc: Subramanian Sriram <sriram-s@hpe.com>
Cc: El-Haj-Mahmoud Samer <samer.el-haj-mahmoud@hpe.com>
Cc: Ye Ting <ting.ye@intel.com>
Cc: Fu Siyuan <siyuan.fu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jiaxin Wu <jiaxin.wu@intel.com>
Reviewed-by: Fu Siyuan <siyuan.fu@intel.com>
Reviewed-by: Ye Ting <ting.ye@intel.com>