fdo#82183 do not reset globals while loading a document

Destroying the function list while an instance of the Formula Wizard is
still open is a bad idea. Workaround not doing this when loading a
document due to a DDE function or external reference being entered in
the wizard.

(cherry picked from commit c0aba5007b6e468336b41138f099914c32f4b0cf)

init formula options once, fdo#82183

(cherry picked from commit 10b6bda51c9da5429ca562c70ce75ee03e5f4e56)

Change-Id: I6fa00fb4f442bf7c9410679e446ff460289e4b16
Reviewed-on: https://gerrit.libreoffice.org/11063
Reviewed-by: Christian Lohmaier <lohmaier+LibreOffice@googlemail.com>
Tested-by: Christian Lohmaier <lohmaier+LibreOffice@googlemail.com>