fwlib: don't add the object file the final archive twice
fwlib: don't add the object file the final archive twice

Some static libraries from the same project include the same
object file twice. This result in duplicated symbols which are
harmless, but that add noise trying to detect the ones that
are really duplicated

multipath-rtp/cerbero,nirbheek/cerbero,ikonst/cerbero,shoreflyer/cerbero,EricssonResearch/cerbero,ramaxlo/cerbero,OptoFidelity/cerbero,ford-prefect/cerbero,lubosz/cerbero,sdroege/cerbero,BigBrother-International/gst-cerbero,freedesktop-unofficial-mirror/gstreamer-sdk__cerbero,ramaxlo/cerbero,ikonst/cerbero,atsushieno/cerbero,lubosz/cerbero,jackjansen/cerbero,flexVDI/cerbero,freedesktop-unofficial-mirror/gstreamer__cerbero,nzjrs/cerbero,GStreamer/cerbero,centricular/cerbero,centricular/cerbero,superdump/cerbero,brion/cerbero,sdroege/cerbero,OptoFidelity/cerbero,BigBrother-International/gst-cerbero,davibe/cerbero,GStreamer/cerbero,brion/cerbero,EricssonResearch/cerbero,freedesktop-unofficial-mirror/gstreamer-sdk__cerbero,multipath-rtp/cerbero,justinjoy/cerbero,shoreflyer/cerbero,jackjansen/cerbero,nirbheek/cerbero-old,freedesktop-unofficial-mirror/gstreamer__cerbero,brion/cerbero,nzjrs/cerbero,atsushieno/cerbero,GStreamer/cerbero,atsushieno/cerbero,EricssonResearch/cerbero,freedesktop-unofficial-mirror/gstreamer__cerbero,lubosz/cerbero,ford-prefect/cerbero,BigBrother-International/gst-cerbero,ikonst/cerbero,AlertMe/cerbero,AlertMe/cerbero,cee1/cerbero-mac,shoreflyer/cerbero,superdump/cerbero,nirbheek/cerbero,ylatuya/cerbero,fluendo/cerbero,BigBrother-International/gst-cerbero,cee1/cerbero-mac,ramaxlo/cerbero,sdroege/cerbero,jackjansen/cerbero,ikonst/cerbero,flexVDI/cerbero,sdroege/cerbero,freedesktop-unofficial-mirror/gstreamer__sdk__cerbero,cee1/cerbero-mac,fluendo/cerbero,justinjoy/cerbero,freedesktop-unofficial-mirror/gstreamer__cerbero,OptoFidelity/cerbero,flexVDI/cerbero,GStreamer/cerbero,freedesktop-unofficial-mirror/gstreamer-sdk__cerbero,fluendo/cerbero,AlertMe/cerbero,cee1/cerbero-mac,freedesktop-unofficial-mirror/gstreamer-sdk__cerbero,davibe/cerbero,nirbheek/cerbero,multipath-rtp/cerbero,BigBrother-International/gst-cerbero,ylatuya/cerbero,fluendo/cerbero,davibe/cerbero,atsushieno/cerbero,centricular/cerbero,AlertMe/cerbero,centricular/cerbero,shoreflyer/cerbero,nirbheek/cerbero-old,freedesktop-unofficial-mirror/gstreamer__sdk__cerbero,superdump/cerbero,superdump/cerbero,davibe/cerbero,OptoFidelity/cerbero,shoreflyer/cerbero,ylatuya/cerbero,nirbheek/cerbero-old,freedesktop-unofficial-mirror/gstreamer__sdk__cerbero,brion/cerbero,ramaxlo/cerbero,multipath-rtp/cerbero,freedesktop-unofficial-mirror/gstreamer__sdk__cerbero,sdroege/cerbero,justinjoy/cerbero,nzjrs/cerbero,jackjansen/cerbero,nzjrs/cerbero,EricssonResearch/cerbero,ylatuya/cerbero,ikonst/cerbero,flexVDI/cerbero,flexVDI/cerbero,nirbheek/cerbero,multipath-rtp/cerbero,atsushieno/cerbero,nirbheek/cerbero-old,EricssonResearch/cerbero,ramaxlo/cerbero,brion/cerbero,AlertMe/cerbero,nzjrs/cerbero,ford-prefect/cerbero,GStreamer/cerbero,fluendo/cerbero,justinjoy/cerbero,freedesktop-unofficial-mirror/gstreamer-sdk__cerbero,ford-prefect/cerbero,centricular/cerbero,lubosz/cerbero