xmerge: The if statement is redundant

Change-Id: I56c5727470c4dba9ffa7c298fb6ccea5be750f33
Reviewed-on: https://gerrit.libreoffice.org/11894
Reviewed-by: Noel Grandin <noelgrandin@gmail.com>
Tested-by: Noel Grandin <noelgrandin@gmail.com>