As reported at e.g.
<https://ask.libreoffice.org/en/question/90346/building-libreoffice-in-cygwin-leads-to-infinite-loop/>,
sometimes MSVC (seen with 2013 on libreoffice-5-2, but there is no
indication that 2015 on master would be different) emits CR characters
at the end of filenames, resulting in unnecessary rebuilds at per-module
builds, and actually to an infinite loop when doing toplevel make.

Given that CR characters are unexpected in any filenames, it should be
safe to just strip those away unconditionally.

Change-Id: I3d56670b4d930a32489f889085711bfd436de82a
Reviewed-on: https://gerrit.libreoffice.org/40452Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Miklos Vajna <vmiklos@collabora.co.uk>