After the gettext migration there is no point to have two
APIs for reading the same .mo file.

This patch is for sc/source/ui/[a-d]* for easier review.

Change-Id: If268fb87ab09ca430a5bdb5cdd53a233e9158bfe
Reviewed-on: https://gerrit.libreoffice.org/54134Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Julien Nabet <serval2412@yahoo.fr>