...as nH needs to fit into the following SwPosSize::Height call's parameter of
type sal_uInt16.  And whatever the reason to check for < instead of
<= USHRT_MAX...

Change-Id: I0377d51e7411eef7913d951eb972214a8d8d5768
Reviewed-on: https://gerrit.libreoffice.org/49065Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>