Add support for uint16_t to RESCALE

Update ref-model RESCALE op to support UINT16 conversions
Add testing for RESCALE UINT16 and ERROR_IFs

Signed-off-by: Jeremy Johnson <jeremy.johnson@arm.com>
Change-Id: Ic6e6e53de1f0b054bedb9e6ba3856e7475498aba
diff --git a/reference_model/src/ops/op_factory.cc b/reference_model/src/ops/op_factory.cc
index 6edd63f..f7ded9a 100644
--- a/reference_model/src/ops/op_factory.cc
+++ b/reference_model/src/ops/op_factory.cc
@@ -396,7 +396,11 @@
             DEF_FACTORY_RANK0_6_ONE_RANK_TWO_TYPE(OpRescale, INT48, INT16);
             DEF_FACTORY_RANK0_6_ONE_RANK_TWO_TYPE(OpRescale, INT48, INT32);
             DEF_FACTORY_RANK0_6_ONE_RANK_TWO_TYPE(OpRescale, UINT8, INT8);
+            DEF_FACTORY_RANK0_6_ONE_RANK_TWO_TYPE(OpRescale, UINT8, INT16);
+            DEF_FACTORY_RANK0_6_ONE_RANK_TWO_TYPE(OpRescale, UINT16, INT16);
             DEF_FACTORY_RANK0_6_ONE_RANK_TWO_TYPE(OpRescale, INT8, UINT8);
+            DEF_FACTORY_RANK0_6_ONE_RANK_TWO_TYPE(OpRescale, INT16, UINT8);
+            DEF_FACTORY_RANK0_6_ONE_RANK_TWO_TYPE(OpRescale, INT16, UINT16);
             break;
 
         // custom