ShellPkg: remove high bit to change a EFI_STATUS to a SHELL_STATUS

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jaben Carsey <Jaben.carsey@intel.com>
Reviewed-by: Eric Dong <eric.dong@intel.com>

git-svn-id: svn://svn.code.sf.net/p/edk2/code/trunk/edk2/ShellPkg@14484 6f19259b-4bc3-4df7-8a09-765794883524
ShellPkg: Added Aarch64 support

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Harry Liebel <Harry.Liebel@arm.com>
Signed-off-by: Olivier Martin <olivier.martin@arm.com>
reviewed-by: Jaben Carsey <jaben.carsey@intel.com>

git-svn-id: svn://svn.code.sf.net/p/edk2/code/trunk/edk2/ShellPkg@14485 6f19259b-4bc3-4df7-8a09-765794883524