Revert "libreofficekit does not work with libmerged"

Instead, we need to make sure it works with libmerged too :-)

This reverts commit 4e9d8ca44a246653894559f10bf88effba366b10.
LibreOfficeKit: Check for libmerged too.

And avoid some strcat's when at it.

Change-Id: I0c70ee2a1abf0c9e2914f756b06bedc3a16df19b