createPath documentation advises against relying on the E_EXIST error code,
so we just ignore it

Change-Id: I0e842315e1fd5c661d2b504b196e320f84c58e4f
Reviewed-on: https://gerrit.libreoffice.org/32081Reviewed-by: Samuel Mehrbrodt <Samuel.Mehrbrodt@cib.de>
Tested-by: Samuel Mehrbrodt <Samuel.Mehrbrodt@cib.de>