Fix RPATH for Vates widgets library

libMantidVatesSimpleGuiViewWidgetsQt4.so is dependant on
libMantidVatesSimpleGuiQtWidgetsQt4.so which was previously not being
found due to the RPATH not searcing in the same directory.

Without this change the Vates Simple Interface is not available.

qt/paraview_ext/VatesSimpleGui/ViewWidgets/CMakeLists.txt

@@ -136,7 +136,7 @@ mtd_add_qt_library (TARGET_NAME VatesSimpleGuiViewWidgets
     @loader_path/../../Contents/MacOS
     @loader_path/../../Contents/Libraries
   LINUX_INSTALL_RPATH
-    "\$ORIGIN/../../${LIB_DIR}"
+    "\$ORIGIN/../../${LIB_DIR};\$ORIGIN"
 )
 
 # Set the name of the generated library