@retval EFI_SUCCESS User identifier returned successfully.\r
@retval EFI_NOT_READY No user identifier can be returned.\r
@retval EFI_ACCESS_DENIED The user has been locked out of this user credential.\r
@retval EFI_INVALID_PARAMETER This is NULL, or Identifier is NULL.\r
@retval EFI_NOT_FOUND User is not NULL, and the specified user handle can't be\r
found in user profile database.\r
@retval EFI_SUCCESS User identifier returned successfully.\r
@retval EFI_NOT_READY No user identifier can be returned.\r
@retval EFI_ACCESS_DENIED The user has been locked out of this user credential.\r
@retval EFI_INVALID_PARAMETER This is NULL, or Identifier is NULL.\r
@retval EFI_NOT_FOUND User is not NULL, and the specified user handle can't be\r
found in user profile database.\r