[ref model] Change RescaleOp attrs to inputs

This patch implements changes required for RescaleOp's
multiplier and shift changing from attributes to inputs

Signed-off-by: Tai Ly <tai.ly@arm.com>
Change-Id: I178919727e3220c749dad0ebce141e695868fee0
diff --git a/examples/test_add_1x4x4x4_f32/model.pb b/examples/test_add_1x4x4x4_f32/model.pb
index f1af89b..026dcea 100644
--- a/examples/test_add_1x4x4x4_f32/model.pb
+++ b/examples/test_add_1x4x4x4_f32/model.pb
@@ -92,5 +92,5 @@
   }
 }
 versions {
-  producer: 1597
+  producer: 1581
 }