ShellPkg: Clean-up 'map' command error message handling
ShellPkg: Clean-up 'map' command error message handling

Refactor 'map' command error handling code and add standard error message

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Tapan Shah <tapandshah@hpe.com>
Reviewed-by: Jaben Carsey <jaben.carsey@intel.com>

git-svn-id: 3158a46dfd52e07d1fda3e32e1ab2e353a00b20f@19616 6f19259b-4bc3-4df7-8a09-765794883524

MattDevo/edk2,MattDevo/edk2,MattDevo/edk2,MattDevo/edk2,MattDevo/edk2,MattDevo/edk2,MattDevo/edk2,MattDevo/edk2