Add Data store to CMake args.

Author: cailafinn

conda/recipes/mantiddocs/build.sh

@@ -28,6 +28,7 @@ LD_PRELOAD="" \
   -DCONDA_BUILD=True \
   -DUSE_PYTHON_DYNAMIC_LIB=OFF \
   -DPython_EXECUTABLE=$PYTHON \
+  -DMANTID_DATA_STORE="/mantid_data" \
   -GNinja \
   ../