sensor: Modify mako template to generate sensor getter func

Change-Id: If198d9a9fb1145bbaeda528e3f80356527b80059
Signed-off-by: Tom Joseph <tomjoseph@in.ibm.com>
diff --git a/types.hpp b/types.hpp
index 330a8a6..41dddd9 100644
--- a/types.hpp
+++ b/types.hpp
@@ -117,6 +117,7 @@
    Exponent exponentB;
    ScaledOffset scaledOffset;
    std::function<uint8_t(SetSensorReadingReq&, const Info&)> updateFunc;
+   std::function<GetSensorResponse(const Info&)> getFunc;
    Mutability mutability;
    DbusInterfaceMap propertyInterfaces;
 };