Disable test on Linux x86 that makes plain 'make' fail due to -mpfmath=387

...rounding issues, and thus caused LO Flathub builds to fail, see
<https://flathub.org/builds/#/builders/3/builds/280>.

Change-Id: I91e8662e0a85b4ed8b16719eed4ade3397edfa0c

sd/qa/unit/import-tests.cxx

@@ -289,7 +289,14 @@ void SdImportTest::testDocumentLayout()
         { "tdf90403.pptx", "xml/tdf90403_", PPTX, -1 },
         { "tdf90338.odp", "xml/tdf90338_", ODP, PPTX },
         { "tdf92001.odp", "xml/tdf92001_", ODP, PPTX },
+// GCC -mpfmath=387 rounding issues in lclPushMarkerProperties
+// (oox/source/drawingml/lineproperties.cxx); see mail sub-thread starting at
+// <https://lists.freedesktop.org/archives/libreoffice/2016-September/
+// 075211.html> "Re: Test File: sc/qa/unit/data/functions/fods/chiinv.fods:
+// fails with Assertion" for how "-mfpmath=sse -msse2" would fix that:
+#if !(defined LINUX && defined X86)
         { "tdf100491.pptx", "xml/tdf100491_", PPTX, -1 },
+#endif
         { "tdf109317.pptx", "xml/tdf109317_", PPTX, ODP},
         // { "pptx/n828390.pptx", "pptx/xml/n828390_", PPTX, PPTX }, // Example
     };