Make the shell be the first boot option by default,
So it can boot into UEFI Internal Shell directly
Signed-off-by: Zhiguang Liu <zhiguang.liu@intel.com> Cc: Jordan Justen <jordan.l.justen@intel.com> Cc: Andrew Fish <afish@apple.com> Cc: Ray Ni <ray.ni@intel.com> Reviewed-by: Ray Ni <ray.ni@intel.com>