tiff: output libtiff error via SAL_WARN for failures

Change-Id: Iff62f8081d5d7b1971940775bd72722f376bf3d0
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/134716
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
diff --git a/vcl/source/filter/itiff/itiff.cxx b/vcl/source/filter/itiff/itiff.cxx
index dde8a1f..f919cda 100644
--- a/vcl/source/filter/itiff/itiff.cxx
+++ b/vcl/source/filter/itiff/itiff.cxx
@@ -219,6 +219,10 @@ bool ImportTiffGraphicImport(SvStream& rTIFF, Graphic& rGraphic)
            bOk = TIFFRGBAImageGet(&img, nullptr, w, img.height);
            TIFFRGBAImageEnd(&img);
        }
        else
        {
            SAL_WARN("filter.tiff", "cannot import tiff, error is: " << emsg);
        }

        access.reset();
        accessAlpha.reset();