Define out code that does not compile for x64

* src/config-dialog.c (config_dialog_box): Define out for x64
* src/olflange-dlgs.c (GPGOptionsDlgProc): Define out call to
  SetWindowLong

This code is only used in older outlook versions which are not
avaibale for 64 bit. And I rather not compile it then change it
and cause regressions in those versions.