xmerge: javadoc <code>..</code> fix

Change-Id: I44b7014d01e481a69c514fc52ffb7e0bf09999e5
Reviewed-on: https://gerrit.libreoffice.org/10571
Reviewed-by: Noel Grandin <noelgrandin@gmail.com>
Tested-by: Noel Grandin <noelgrandin@gmail.com>