NetworkPkg/IpsecConfig: remove module-local ARRAY_SIZE macro

NetworkPkg/IpsecConfig: remove module-local ARRAY_SIZE macro

Rely on the central macro definition from "MdePkg/Include/Base.h" instead.

Cc: Jiaxin Wu <jiaxin.wu@intel.com>
Cc: Siyuan Fu <siyuan.fu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Fu Siyuan <siyuan.fu@intel.com>
Reviewed-by: Wu Jiaxin <jiaxin.wu@intel.com>
Reviewed-by: Jordan Justen <jordan.l.justen@intel.com>