ShellPkg/MV: Fix MV to deny moving parent of current directory

ShellPkg/MV: Fix MV to deny moving parent of current directory

When user types "mv -r fs0:\A\ fs1:\" under directory
"fs0:\A\B\", MV command should deny such movement.

The patch fixes the above issue.
It also denies moving current directory.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Chen A Chen <chen.a.chen@intel.com>
Reviewed-by: Jaben Carsey <jaben.carsey@intel.com>
Reviewed-by: Ruiyu Ni <ruiyu.ni@intel.com>