fix clang-plugin and --disable-pdfimport build

Change-Id: Ie7ae85bcee75ee6990962d1ce9f9cbd4d3327d82
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/191190
Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>
Tested-by: Jenkins

svx/qa/unit/svdraw.cxx

@@ -64,10 +64,13 @@ public:
     }
 
     void setUp() override;
+
+#if ENABLE_PDFIMPORT
     uno::Reference<xml::crypto::XXMLSecurityContext>& getSecurityContext()
     {
         return mxSecurityContext;
     }
+#endif
 
 protected:
     SdrPage* getFirstDrawPageWithAssert();